I wonder if you are, maybe accidentally, implying that any president before has made America weaker?
I'd argue that actively trying to make enemies out of friends is in no way going to make America stronger. Quite the opposite.
You're going to have a very uphill battle making a case that he's making America stronger in any commonly held definition of the word. Partisanship is a hell of a drug, man...
Please explain / define how America is "strong" today?
I think fundamentally there is a difference in the definition of “America” at play here too.