It depends who we’re talking about.
The sovereign citizen types, the militias, commando cosplayers . . . they were always 100% in favor of shooting at cops. But my impression is the people who love the “blue lives matter” slogan are mostly cops and more mainstream conservatives who think they have to choose between cops and criminals. They willfully ignore that cops can be criminals too.
And there is a difference between federal agents and regular police, too. Fox News loves to demonize federal agents, but they will grant sainthood to the local thug-in-blue, and side with him over anyone he might kill or arrest. Even during Obama’s presidency.