Trump is a new problem. It can take time to figure out how to solve a new problem.
How were you expecting them to handle him?
You're actually asking why they couldn't handle him quickly. He may end up handled in the sense of not getting the nomination. It also seems as though it took Trump's proposal to not let Muslims enter the US to really motivate the Republican heavyweights.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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