It's called the 'Gish Gallop.'

The best way for the Right to defeat the Left in an argument is to unload a torrent of lies, half truths, complete nonsense, and other disinformation. The idea is to overwhelm the other side's ability to form a coherent response, because there's too much to unpack.

Trump knows Kennedy is an idiot, but he's a useful idiot in that he forces the Left to deal with him.