I hope that's all this is. Trump is my candidate. I think Cruz will be weak in the general election, even against Hillary. But if Trump really tries to sue Cruz or persists in demanding another caucus, both futile gestures, he's going to look both weak and unhinged, a deadly combo in politics.
If he is serious he's making a rookie error. Taking a tactic that can work in business negotiations - threatening or even filing lots of trivial lawsuits to put the other side off balance and intimidate them - and trying it in the public world of politics where the more litigious side often loses the PR battle even if they prevail in court.
And in this case it's clear that Trump will not prevail in either arena.
Well-said.