I want to start by saying that I would never presume to tell someone how they should react to a situation like this. If some of you feel like your best response is to boycott, that is entirely your business.
On the other hand, my personal feelings are that those countries don't care and won't even know that you are boycotting them at Disney World. The CM's from the country involved and Disney will be the ones that suffer.
Call me silly if you want. I always feel a little like an ambassador when I'm in the World Showcase. I try to make up for the tourists that are disagreeable to be around. I always try to be cheerful and pleasant to CM's, but in World Showcase I try even harder. I take an interest in where they are from and let them tell me about their home. I feel like those people are guests in our country and I want them to go home with good feelings about us. Who knows, the person you are kind to might be making decisions at the UN someday. In this day and time, our country can use all the friends it can get around the world. This may be even more true in the countries that are taking a stand against us. Just something to think about.