I launched my Kickstarter project (
http://bit.ly/talonmount) and enabled international shipment for rewards due to potential global appeal.
I did not "add a fee" to ship to backers outside the USA, thinking I could charge a fee separately since shipping costs may vary based on ship-to geographic locations and speed of delivery.
Now that I am being messaged for international shipping costs and due to uncertainties whether or not I can charge added shipping prices to my international backers, prior to launch I should have added a flat-rate international shipping fee; or replicated my rewards one for domestic and another for international shipping.