You really don't want soldiers patrolling streets and stopping crime. That's a violation of the Posse Comitatus Act of 1878, and the reason why that act exists is so that you don't have a military dictatorship where soldiers routinely detain civilians. For that matter, this whole deployment is a violation of Posse Comitatus.

It would be better if soldiers were never deployed on domestic soil. However, given that they are, it is far better that they sit around making Trump look like a tough guy at taxpayer expense than that they actually do anything.

It's not about stopping crime. It's about normalizing the sight of armed troops in cities.

Trump has already stated many times, not jokingly that he wants a third term. He acknowledges that he can't be elected for a third term. However a number of legal "experts", including noted crackpot Alan Dershowitz, have noted that election is not the only route to a third term.