Trump said "wouldn't you love to see one of these NFL owners..." That is not demanding they all get fired. 

The NFL is 70% black, and they are some of the highest-paid professionals on the entire planet. Maybe they go to another country, one of those much fairer places, to play? Oh wait nobody else cares about football. 

I'm saying maybe come up with some actual demands / things you're protesting specifically. Rosa Parks was protesting the fact that public transport was segregated. These players are not oppressed in the slightest. I would be happy to stand behind them if they had something specific they wanted to change, instead of hijacking the national anthem to protest some general feeling of inequality.