Trump beat Cruz in all the other debates, particularly the last one where Cruz came out in favor of cheap plastic goods from China. The result, combined with Cruz's other missteps over the weekend, was that Cruz failed to win even one state.
I do not think at this point there's any credibility in Cruz's vanity that Trump decided to cancel because of Cruz. It has more to do with the fact that the RNC promised 8 or 9 debates, and then just a few days ago made plans for yet another one.
Serious question.
Given that the objective is to defeat Clinton.
And given that the party is close to equally divided between trump and Cruz,
How would YOU unite the party, and what is the probability that your plan will succeed?