To answer your questions:
Black lives matter only in certain specific cases.
1. If a gentle giant of a black man, suspected of a recent crime, is shot by a white policeman during a physical altercation.
2. If a young black man is shot by a white Hispanic neighborhood watch volunteer during a physical altercation.
3. If a young black man dies of injuries suffered in riding in a police van in police custody.
Otherwise black lives really don’t matter to the black/liberal/radical activists. Black lives only matter in certain specific circumstances.
(sarcasm)