it's a dict

tasks/shorewall.yml

@@ -9,7 +9,7 @@
   package:
     name: "{{ item }}"
     state: "{{ shorewall_package_state }}"
-  with_items: shorewall_packages
+  with_items: "{{ shorewall_packages }}"
   notify: 
     - enable shorewall
   tags:
@@ -55,4 +55,4 @@
     tags:
       - configuration
   when: (shorewall_package_state != "absent")
-  
\ No newline at end of file
+