No one seems to care about context. This is especially true if the context makes them uncomfortable, maybe doubly so if it's about race. Look, sometimes there are real problems that may put white, heterosexual Christians at the wrong end of history, but it doesn't mean that you, as a white, heterosexual Christian are the problem. You aren't obligated to feel guilty or bad about it, but at the same time, it doesn't mean there is no problem.
For example, a popular response to #blacklivesmatter is to suggest that all lives matter. Well yeah, of course, but that response completely trivializes the fact that there is a real socioeconomic problem that puts a large population at risk. "All lives matter" suggests that the problems don't need to be addressed or don't exist. Objectively, with data, we can logically conclude that a million different factors put people in a cycle of poverty, poor education and violence that is difficult to break.
This doesn't mean that people are at war. No one is suggesting that a pattern of abuse and racism on the part of some police departments means all police are evil. I've known a lot of police, and all were professional, excellent people. These are not mutually exclusive categories of people: Both can exist.
So yes, I get it. It is vitally important that we partner with and support our law enforcement. But as soon as you view that support as a side that is diametrically opposed to bringing up the real problems that many communities face with their local police departments, you're sweeping a civil rights problem under the rug. More division gets us nowhere. Two centuries of racial inequality is a very real, unsolved problem. Don't trivialize it.