Sadly I feel like this will result in the Kennedy Center being closed or at least largely defunded due to a lack of profitability.
At the same time, I don't plan on attending anything there in the next few years because of this change. It really is a lose-lose situation.
Definitely go if you can. I've never experienced any sort of discrimination based on my American nationality in Europe. In general, I think it's assumed that if you're willing to travel and are respectful of the local culture you aren't one of the bad ones. You might get a few questions about your experiences or feelings about the current situation, but that's the most I've seen.
That said, some cities have recently become pretty anti-tourism in general, especially in Spain and Italy from what I've heard. But this isn't against Americans, it's against all tourists driving up housing prices.
No penis