Donald Trump arrives Thursday on Capitol Hill for a Republican congressional confab that's looking more like a showdown than a kumbaya moment for the party’s presumed presidential nominee.
Billed as an opportunity to unify the GOP after a blistering primary season, the morning meet-and-greets will be anything but that.
House Speaker Paul D. Ryan has surprised many by refusing to endorse Trump. Their open friction led to speculation earlier this week that Ryan might not serve as chairman of the Republican National Convention this summer, though Trump said Wednesday morning he hoped Ryan would.
At the same time,...