diff --git a/resources/sql/autopatches/20220401.phameinteract.04.postinteract.sql b/resources/sql/autopatches/20220401.phameinteract.04.postinteract.sql
new file mode 100644
--- /dev/null
+++ b/resources/sql/autopatches/20220401.phameinteract.04.postinteract.sql
@@ -0,0 +1,6 @@
+ALTER TABLE {$NAMESPACE}_phame.phame_post
+  ADD interactPolicy VARBINARY(64) NOT NULL;
+
+UPDATE {$NAMESPACE}_phame.phame_post
+  SET interactPolicy = 'obj.phame.blog'
+  WHERE interactPolicy = '';
diff --git a/src/__phutil_library_map__.php b/src/__phutil_library_map__.php
--- a/src/__phutil_library_map__.php
+++ b/src/__phutil_library_map__.php
@@ -5277,6 +5277,7 @@
     'PhameDescriptionView' => 'applications/phame/view/PhameDescriptionView.php',
     'PhameDraftListView' => 'applications/phame/view/PhameDraftListView.php',
     'PhameHomeController' => 'applications/phame/controller/PhameHomeController.php',
+    'PhameInheritBlogPolicyRule' => 'applications/phame/policyrule/PhameInheritBlogPolicyRule.php',
     'PhameLiveController' => 'applications/phame/controller/PhameLiveController.php',
     'PhameNextPostView' => 'applications/phame/view/PhameNextPostView.php',
     'PhamePost' => 'applications/phame/storage/PhamePost.php',
@@ -12167,6 +12168,7 @@
     'PhameDescriptionView' => 'AphrontTagView',
     'PhameDraftListView' => 'AphrontTagView',
     'PhameHomeController' => 'PhamePostController',
+    'PhameInheritBlogPolicyRule' => 'PhabricatorPolicyRule',
     'PhameLiveController' => 'PhameController',
     'PhameNextPostView' => 'AphrontTagView',
     'PhamePost' => array(
diff --git a/src/applications/phame/editor/PhamePostEditor.php b/src/applications/phame/editor/PhamePostEditor.php
--- a/src/applications/phame/editor/PhamePostEditor.php
+++ b/src/applications/phame/editor/PhamePostEditor.php
@@ -21,6 +21,8 @@
 
   public function getTransactionTypes() {
     $types = parent::getTransactionTypes();
+
+    $types[] = PhabricatorTransactions::TYPE_INTERACT_POLICY;
     $types[] = PhabricatorTransactions::TYPE_COMMENT;
 
     return $types;
diff --git a/src/applications/phame/policyrule/PhameInheritBlogPolicyRule.php b/src/applications/phame/policyrule/PhameInheritBlogPolicyRule.php
new file mode 100644
--- /dev/null
+++ b/src/applications/phame/policyrule/PhameInheritBlogPolicyRule.php
@@ -0,0 +1,51 @@
+<?php
+
+final class PhameInheritBlogPolicyRule
+  extends PhabricatorPolicyRule {
+
+  public function getObjectPolicyKey() {
+    return 'phame.blog';
+  }
+
+  public function getObjectPolicyName() {
+    return pht('Same as Blog');
+  }
+
+  public function getPolicyExplanation() {
+    return pht('Use the same policy as the parent blog.');
+  }
+
+  public function getRuleDescription() {
+    return pht('inherit from blog');
+  }
+
+  public function getObjectPolicyIcon() {
+    return 'fa-feed';
+  }
+
+  public function canApplyToObject(PhabricatorPolicyInterface $object) {
+    return ($object instanceof PhamePost);
+  }
+
+  public function applyRule(
+    PhabricatorUser $viewer,
+    $value,
+    PhabricatorPolicyInterface $object) {
+
+    // TODO: This is incorrect in the general case, but: "PolicyRule" currently
+    // does not know which capability it is evaluating (so we can't test for
+    // the correct capability); and "PhamePost" currently has immutable view
+    // and edit policies (so we can only arrive here when evaluating the
+    // interact policy).
+
+    return PhabricatorPolicyFilter::hasCapability(
+      $viewer,
+      $object->getBlog(),
+      PhabricatorPolicyCapability::CAN_INTERACT);
+  }
+
+  public function getValueControlType() {
+    return self::CONTROL_TYPE_NONE;
+  }
+
+}
diff --git a/src/applications/phame/storage/PhamePost.php b/src/applications/phame/storage/PhamePost.php
--- a/src/applications/phame/storage/PhamePost.php
+++ b/src/applications/phame/storage/PhamePost.php
@@ -27,6 +27,7 @@
   protected $blogPHID;
   protected $mailKey;
   protected $headerImagePHID;
+  protected $interactPolicy;
 
   private $blog = self::ATTACHABLE;
   private $headerImageFile = self::ATTACHABLE;
@@ -40,7 +41,10 @@
       ->setBlogPHID($blog->getPHID())
       ->attachBlog($blog)
       ->setDatePublished(PhabricatorTime::getNow())
-      ->setVisibility(PhameConstants::VISIBILITY_PUBLISHED);
+      ->setVisibility(PhameConstants::VISIBILITY_PUBLISHED)
+      ->setInteractPolicy(
+        id(new PhameInheritBlogPolicyRule())
+          ->getObjectPolicyFullKey());
 
     return $post;
   }
@@ -140,6 +144,8 @@
         // T6203/NULLABILITY
         // This one probably should be nullable?
         'datePublished' => 'epoch',
+
+        'interactPolicy' => 'policy',
       ),
       self::CONFIG_KEY_SCHEMA => array(
         'key_phid' => null,
@@ -196,6 +202,7 @@
     return array(
       PhabricatorPolicyCapability::CAN_VIEW,
       PhabricatorPolicyCapability::CAN_EDIT,
+      PhabricatorPolicyCapability::CAN_INTERACT,
     );
   }
 
@@ -220,6 +227,8 @@
         } else {
           return PhabricatorPolicies::POLICY_NOONE;
         }
+      case PhabricatorPolicyCapability::CAN_INTERACT:
+        return $this->getInteractPolicy();
     }
   }
 
@@ -230,6 +239,8 @@
       case PhabricatorPolicyCapability::CAN_VIEW:
       case PhabricatorPolicyCapability::CAN_EDIT:
         return ($user->getPHID() == $this->getBloggerPHID());
+      case PhabricatorPolicyCapability::CAN_INTERACT:
+        return false;
     }
   }