Ms. Cheney’s ambitions reflect a greater tension within the Republican Party as a younger generation feels less reluctance to challenge incumbents in the party, especially if they are seen as too consensus-minded or insufficiently conservative. snip What has startled some people here is not just the fact that Ms. Cheney is seemingly trying to nudge Mr. Enzi into retirement, but that she appears to be doing so with a hand from her father. snip Ms. Cheney’s broader line of attack on Mr. Enzi, though, may be that he is too willing to work with Democrats and not vocal enough in...