[Sopater]

Where does the Constitution authorize fedgov to supply local police in the first place?

It does not. The Federal government has no business supplying local police with anything.

If you can't find where it does so, then how is ending or curtailing an unconstitutional fedgov action a power grab by fedgov?

I don't recall ever saying anything about a "power grab". Perhaps you have me confused with someone else.

The federal gov't has no constitutional authority to either provide nor limit local governments acquisition of any equipment. That's all I'm saying.

[MrB]

I’m not so sure they were “supplying” them to the local leos.
I think they just had a surplus and were selling them cheap,
but only to law enforcement.
Can’t have Billy Bob driving an MRAP around town, now can we?