POTUS cannot deploy police. That's up to each State. Trump made the military available for action in the case of inaction by the States. Trump is doing this so it looks like he is doing something. And it's the right thing. What's so hard to understand?
I just give up. If you cannot see that rioters rioting do not trump everyone else's rights (which is what you are essentially calling for because you are afraid of by standers getting hurt), and you don't agree with controlling measures, then the right to assembly cannot be upheld. You understand that rioters use innocent public members to shield them too, right?
When do you escalate then, buka? People are dying. Buildings are being set alight with people INSIDE of them. Personal property is being destroyed. EMS is being prevented from entering areas. Mass looting is taking place. So, tell us when it's acceptable to enforce the law?
Edit:
What does the police are trained as riot control even mean? Are you debating for the police to come in and quell the situation?