There is something to that. I'm thinking Trump may have looked around the table at G-7 and saw individual people (not the countries or the economies they are representative of) whom he views in his own mind as "weak". Heck, those same people might not even be there for the next meeting as they are subject to the political whims of the nations they represent. "Weak."
Trump clearly reserves his own admiration for those whom he views as personally successful in relation to the amount of power they can wield and how absolutely they are able to wield it. Trump came into office and at first showed a clear contempt for Kim Jung Un. One can almost think of Trump being briefed on Kim and his regime and instead of being horrified he slowly begins to come around in his own mind that: "Hey, maybe Kim ain't such a bad kid after all. I mean, really cool parades, his people either worship him or become acquainted the business end of an anti-aircraft gun. Strong."