Hi Sumner, If you dont want to allow shipping outside the US the only option is to remove all the countries except US from the Smith_Countries table.  
  To remove all countries except US do the following:
  1)  Navigate to the dnn host -> SQL menu option 2)  Run the following sql statement :
    delete from Smith_Country where code != 'US'
  Please make sure you have a full backup of your database before executing the above stmt.
  I will add a country and state editor screen to the cart dev roadmap to make it easier to manage countries.  
  Thanks for your feedback! 
										 
											
 At your service, 
Dave Smith
  
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