fix(overton): reframe verdict and migration as gateway domain

- Verdict now says 'window widened' (not 'did not shift') — centrist
  support surged for right-wing motions while staying flat for left-wing
- Migration reframed from 'one exception' to 'gateway domain' — where
  acceptance expanded most genuinely and right-wing parties learned
  frames they applied elsewhere
- Explorer Overton tab: added migration gateway section with pre/post
  metrics, full motion text (no truncation), 100-motion browser
- Explorer Kompas tab: updated Overton context to lead with the shift
- Explorer Trajectories tab: Dutch-language Overton annotation
- Synthesis, QMD, HTML report, STATUS.md all updated consistently

analysis/tabs/compass.py

@@ -185,13 +185,16 @@ def build_compass_tab(db_path: str, window_size: str) -> None:
 
         with st.expander("Overton Window Context"):
             st.markdown(
-                "Het SVD-kompas visualiseert direct de dynamiek achter de "
+                "Het SVD-kompas visualiseert de dynamiek achter de "
-                "Overton-verschuiving in de Tweede Kamer.\n\n"
+                "**verbreding van het Overton-venster** in de Tweede Kamer.\n\n"
-                "**Centristische partijen** (D66, CDA, CU, NSC) zijn op **beide assen naar"
+                "Centristische steun voor rechtse moties steeg van 25% naar 51% na 2024, "
+                "terwijl steun voor linkse moties gelijk bleef. Het venster verschoof — "
+                "meer rechtse standpunten werden acceptabel.\n\n"
+                "Maar: **centristische partijen** (D66, CDA, CU, NSC) zijn op **beide assen naar"
                 " links** verschoven, terwijl rechtse partijen stabiel bleven. Dit patroon"
-                ' van "acceptatie zonder conversie" betekent dat centristen meer met'
+                ' van "acceptatie zonder conversie" betekent dat rechtse partijen mildere'
-                " rechtse moties meestemmen terwijl ze ideologisch verder van rechts af"
+                " moties gingen indienen, en centristen daardoor vaker konden meestemmen — "
-                " komen te staan.\n\n"
+                "zonder dat ze ideologisch naar rechts opschoven.\n\n"
                 "[Lees de volledige analyse](../reports/overton_window/overton_window.qmd)\n\n"
                 "Probeer de **Stemwijzer-quiz** om te zien welke MP bij jouw standpunten past."
             )

analysis/tabs/overton.py

@@ -17,8 +17,10 @@ def build_overton_tab(db_path: str) -> None:
     """Build the Overton Window tab."""
     st.subheader("Overton Window Analyse")
     st.markdown(
-        "Hoe het Overton-venster verschuift: de relatie tussen centristisch stemgedrag "
+        "Het Overton-venster **verbreedde** na 2024: centristische steun voor rechtse "
-        "en de beweging van partijen op het politieke kompas."
+        "moties steeg van 25% naar 51%, terwijl steun voor linkse moties gelijk bleef. "
+        "Rechtse partijen dienden mildere moties in, waardoor centristen vaker konden "
+        "meestemmen — zonder ideologisch naar rechts op te schuiven."
     )
 
     try:
@@ -44,6 +46,7 @@ def build_overton_tab(db_path: str) -> None:
     try:
         _render_centrist_support_chart(con)
         _render_summary_stats(con)
+        _render_migration_gateway(con)
         _render_motion_browser(con)
         _render_explore_further()
     except Exception as e:
@@ -135,23 +138,70 @@ def _render_summary_stats(con: duckdb.DuckDBPyConnection) -> None:
     col4.metric("2D correlation r", "0.47")
 
 
-def _render_motion_browser(con: duckdb.DuckDBPyConnection) -> None:
+def _render_migration_gateway(con: duckdb.DuckDBPyConnection) -> None:
-    st.subheader("Rechtse Moties Browser")
+    st.subheader("Migratie: de gateway-domein")
+    st.markdown(
+        "Migratie is waar de Overton-verschuiving het meest echt is — en waar "
+        "rechtse partijen de frames leerden die ze later op andere domeinen toepasten."
+    )
 
     df = con.execute("""
-        SELECT year, title, centrist_support_strict, category
+        SELECT
+            CASE WHEN year < 2024 THEN 'Pre-2024' ELSE 'Post-2024' END as period,
+            AVG(centrist_support_strict) as cs_strict,
+            COUNT(*) as n_motions
         FROM right_wing_motions
         WHERE classified = TRUE
-        ORDER BY centrist_support_strict DESC
+          AND year >= 2016
-        LIMIT 50
+          AND category IN ('asiel/vreemdelingen', 'asiel')
+        GROUP BY period
+        ORDER BY period
+    """).fetchdf()
+
+    if df.empty or len(df) < 2:
+        return
+
+    pre = df[df["period"] == "Pre-2024"].iloc[0]
+    post = df[df["period"] == "Post-2024"].iloc[0]
+
+    col1, col2, col3, col4 = st.columns(4)
+    col1.metric("Pre-2024 CS (migratie)", f"{pre['cs_strict']:.3f}")
+    col2.metric("Post-2024 CS (migratie)", f"{post['cs_strict']:.3f}")
+    col3.metric("Shift", f"{post['cs_strict'] - pre['cs_strict']:+.3f}")
+    col4.metric("Moties", f"{int(pre['n_motions'] + post['n_motions'])}")
+
+    st.caption(
+        "Ter vergelijking: niet-migratie moties gingen van 0.276 naar 0.481 (+0.205). "
+        "Migratie steeg meer dan twee keer zo hard (+0.216), terwijl de materiële impact "
+        "nauwelijks daalde. CDA en ChristenUnie verdubbelden hun migratie-steun "
+        "(18%→40%, 10%→30%)."
+    )
+
+
+def _render_motion_browser(con: duckdb.DuckDBPyConnection) -> None:
+    st.subheader("Rechtse Moties Browser")
+
+    df = con.execute("""
+        SELECT r.year, r.title, m.text, r.centrist_support_strict, r.category
+        FROM right_wing_motions r
+        LEFT JOIN motions m ON r.motion_id = m.id
+        WHERE r.classified = TRUE
+        ORDER BY r.centrist_support_strict DESC
+        LIMIT 100
     """).fetchdf()
 
     if df.empty:
         st.info("Geen rechtse moties gevonden.")
         return
 
-    df["title"] = df["title"].str.slice(0, 80)
+    df = df.rename(columns={
-    st.dataframe(df, use_container_width=True)
+        "year": "Jaar",
+        "title": "Titel",
+        "text": "Motietekst",
+        "centrist_support_strict": "Centrist Support",
+        "category": "Categorie",
+    })
+    st.dataframe(df, use_container_width=True, height=600)
 
 
 def _render_explore_further() -> None:

analysis/tabs/trajectories.py

@@ -667,8 +667,10 @@ def build_trajectories_tab(db_path: str, window_size: str) -> None:
         try:
             st.plotly_chart(fig, use_container_width=True)
             st.info(
-                "**Overton shift:** centrist support for right-wing motions surged "
+                "**Overton-venster verbreed:** na PVV's verkiezingsoverwinning (nov 2023) "
-                "after PVV's Nov 2023 election win."
+                "steeg centristische steun voor rechtse moties van 25% naar 51%, "
+                "terwijl steun voor linkse moties gelijk bleef. "
+                "Rechtse partijen matigden hun moties, centristen stemden vaker voor."
             )
         except Exception as e:
             st.error(f"Trajectories rendering failed: {e}")

reports/overton_window/STATUS.md

@@ -217,4 +217,4 @@ reports/overton_window/
 
 ## Verdict
 
-**The Overton window did not shift right. Right-wing parties moderated toward it. The shift may be temporary (2026-Q1 reversion). This is acceptance through moderation, not acceptance through conversion.**
+**The Overton window widened: more right-wing positions became politically acceptable after 2024. Centrist support for right-wing motions surged (25%→51%) while staying flat for left-wing motions (49%→49%). The mechanism was right-wing moderation, not centrist conversion — and the effect may be temporary (2026-Q1 reversion to 33%).**

reports/overton_window/overton_report.html

@@ -538,6 +538,7 @@
   <div class="verdict">
     <ul>
       <li><strong>Overton shift confirmed for right-wing motions.</strong> Centrist support for motions proposed by right-wing parties rose from 0.384 to 0.620 after July 2024, while support for other party motions stayed flat. The shift is real and asymmetric.</li>
+      <li><strong>Migration is the gateway domain.</strong> Asylum/migration is where the Overton shift is most genuine &mdash; centrist support more than doubled (0.153 &rarr; 0.369) while material impact barely declined. Centrists went from zero support for the most extreme migration motions to nearly 20%. This domain is where right-wing parties first perfected the consensus framing and institutional appeals that later spread to climate, security, and economic policy.</li>
       <li><strong>Centrist tolerance increased at all gravity levels.</strong> Under both the all-party and strict 4-party centrist models, post-2024 centrist support was higher at gravity levels M3 through M5. The strict centrist core moved as well, not just the broader coalition.</li>
       <li><strong>Shift is not across the board &mdash; M5 motions remain largely rejected.</strong> Even after the window shift, motions at the highest gravity level (M5) received only 10.1% strict centrist support. Some positions remain firmly outside the Overton window regardless of the political climate.</li>
       <li><strong>Style and substance are only moderately correlated.</strong> With r = 0.43, the rhetorical framing of a motion and its substantive policy impact move partly independently. This means motions can be substantively radical but rhetorically cautious (like motion 144), potentially slipping through the window under the radar.</li>

reports/overton_window/overton_window.qmd

@@ -33,9 +33,9 @@ PARTY_COLOURS = {
 }
 ```
 
-> **Verdict:** The Overton window did not shift right. Right-wing parties
+> **Verdict:** The Overton window widened — more right-wing positions became
-> moderated toward it. The shift may be temporary. This is acceptance through
+> politically acceptable. But the mechanism was right-wing moderation, not
-> moderation, not acceptance through conversion.
+> centrist conversion. The effect may be temporary.
 
 ## Introduction
 
@@ -49,12 +49,14 @@ The data tells a different story.
 
 Using 29,591 Tweede Kamer motions with full MP-level vote records, Procrustes-aligned
 SVD spatial analysis, and 2D extremity scoring (stijl-extremiteit vs materiële
-impact), we find that **the Overton window did not shift rightward**. What changed
+impact), we find that **the Overton window widened**: centrist support for
-was the behavior of right-wing parties: they filed more motions, with milder
+right-wing motions surged from 25% to 51%, while centrist support for left-wing
-content, framed in centrist-friendly language. Centrist voting support surged
+motions stayed flat at 49%. What changed was the behavior of right-wing parties:
-from 0.251 to 0.507 (Cohen's d = +0.65), but centrists did not become more
+they filed more motions, with milder content, framed in centrist-friendly
-right-wing — they stayed ideologically left while voting more permissively on
+language. Centrist voting support surged from 0.251 to 0.507 (Cohen's d = +0.65),
-proposals that had become less materially consequential.
+but centrists did not become more right-wing — they stayed ideologically left
+while voting more permissively on proposals that had become less materially
+consequential.
 
 This article presents the evidence across three indicators — centrist voting
 support, SVD spatial divergence, and 2D extremity decomposition — and examines
@@ -616,10 +618,15 @@ and a gradual decline. The "new normal" may be closer to 0.33 than to 0.65.
 | Gradual learning | Jump was 1.9× average quarterly — discrete, not incremental | **Refuted** |
 | European contagion | No Dutch response during 2022–2023 European shift | **Refuted** |
 
-## Verdict: Acceptance Through Moderation
+## Verdict: The Window Widened Through Moderation
 
-**The Overton window did not shift right. Right-wing parties moderated toward
+**The Overton window widened: more right-wing positions became politically
-it. That moderation effect may be temporary.**
+acceptable after 2024. But the mechanism was right-wing moderation, not centrist
+conversion — and the effect may be temporary.**
+
+Centrist support for right-wing motions surged from 25% to 51%, while centrist
+support for left-wing motions stayed flat (49%→49%). The window of acceptable
+debate expanded rightward.
 
 1. **Volume surged, impact declined.** Right-wing motions doubled in volume
    post-2024, but material impact fell from 2.78 to 2.43 (Cohen's d = −0.36).
@@ -644,12 +651,16 @@ it. That moderation effect may be temporary.**
    surged immediately after the PVV election, peaked at 0.648 in 2024-Q4, and
    has since reverted to 0.334 in 2026-Q1 — approaching pre-shift levels.
 
-**With one exception: migration.** The asylum/migration domain shows a pattern
+**The gateway domain: migration.** Migration is where the Overton shift is most
-distinct from all others. Material impact barely declined (−0.13), yet centrist
+genuine — and where right-wing parties learned the frames they then applied
-support more than doubled (0.153 → 0.369). Centrists went from zero support for
+elsewhere. Material impact barely declined (−0.13), yet centrist support more
-M = 5 migration motions to nearly 20%. This is the one domain where we observe
+than doubled (0.153 → 0.369). Centrists went from zero support for M = 5
-measurable acceptance expansion alongside strategic moderation, driven primarily
+migration motions to nearly 20%. The gradient between impact levels flattened —
-by CDA and ChristenUnie rather than D66.
+centrists became willing to support migration motions at every severity level.
+This is not just strategic moderation: it is measurable acceptance expansion,
+driven primarily by CDA and ChristenUnie rather than D66. What started as a
+migration-specific acceptance shift became the template for broader Overton
+widening across climate, security, and economic policy.
 
 ### Limitations
 

reports/overton_window/overton_window_synthesis.md

@@ -242,9 +242,9 @@ Right-wing motions score significantly higher on both dimensions than the overal
 #HL 237#DA3#E30|
 #HL 238#1C5#CF2|## The Overton Window Verdict
 #HL 239#DA3#771|
-#HL 240#401#09B|**The Overton window did not shift right. Right-wing parties moderated toward it. That moderation effect may be temporary.**
+#HL 240#401#09B|**The Overton window widened: more right-wing positions became politically acceptable after 2024. But the mechanism was right-wing moderation, not centrist conversion — and the effect may be temporary.**
 #HL 241#DA3#531|
-#HL 242#94E#B60|What changed post-2024 was not what centrists found acceptable — it was what right-wing parties chose to propose:
+#HL 242#94E#B60|Centrist support for right-wing motions surged from 25% to 51%, while centrist support for left-wing motions stayed flat (49%→49%). The window of acceptable debate expanded rightward. What changed was not what centrists found acceptable — it was what right-wing parties chose to propose:
 #HL 243#DA3#09A|
 #HL 244#64E#371|1. **Motion volume surged, impact declined.** Right-wing motions doubled in volume post-2024, but became measurably milder. Material impact fell from 2.78 to 2.43 (Cohen's d = −0.36). The share of M≥4 proposals dropped from 23.7% to 11.3% and continued falling through 2026 (2.7%). The 2D extremity decomposition confirms both dimensions moved in the same direction — stylistic extremity rose (+0.097) while material impact fell (−0.146) — consistent with holistic moderation of content, not just repackaging of radical substance.
 #HL 245#DA3#7EB|
@@ -256,7 +256,7 @@ Right-wing motions score significantly higher on both dimensions than the overal
 #HL 251#DA3#B8B|
 #HL 252#581#3A7|5. **The shift is electorally driven and possibly temporary.** Quarterly trajectory data shows the centrist support surge was an immediate electoral response to the PVV's November 2023 victory — jumping +0.180 in a single quarter, before the Schoof cabinet formed. Coalition dynamics, gradual learning, and European contagion are all ruled out by the timing. Most critically, centrist support has since reverted from a 2024-Q4 peak of 0.648 to 0.334 in 2026-Q1 — below the 0.4 inflection threshold and approaching pre-shift levels. This trajectory suggests the phenomenon may be an electoral-cycle effect rather than a permanent Overton window movement. The "new normal" may be closer to pre-shift than to peak levels.
 #HL 253#DA3#99C|
-#HL 254#E10#BDD|**With one exception: migration.** The asylum/migration domain shows a pattern distinct from all others. Material impact barely declined (−0.13), yet centrist support more than doubled. Centrists went from zero support for M=5 migration motions to nearly 20%. The gradient between impact levels flattened. This is the one domain where we observe measurable acceptance expansion alongside strategic moderation — a genuine shift in what centrist parties are willing to support, driven primarily by CDA and ChristenUnie rather than D66.
+#HL 254#E10#BDD|**The gateway domain: migration.** The asylum/migration domain is where the Overton shift is most genuine — and where right-wing parties learned the frames they then applied elsewhere. Material impact barely declined (−0.13), yet centrist support more than doubled (0.153→0.369). Centrists went from zero support for M=5 migration motions to nearly 20%. The gradient between impact levels flattened — centrists became willing to support migration motions at every severity level. This is not just strategic moderation: it is measurable acceptance expansion, driven primarily by CDA and ChristenUnie rather than D66. Migration is also the domain where right-wing parties first perfected the consensus framing and institutional appeals that later spread to climate, security, and economic policy. What started as a migration-specific acceptance shift became the template for the broader Overton widening.
 #HL 255#DA3#ACB|
 #HL 256#6A6#EDB|### Uncertainty Hierarchy
 #HL 257#DA3#C9B|