Two stories got me thinking about why Trump backtracked on attacking Ted Cruz, who has emerged as his chief rival by leading in several Iowa polls.

First, there’s the Trump appearance on ABC’s “Jimmy Kimmel Live,” where he sort of admitted to being “a bit divisive” and made a strong call for Republican unity.

‘I would like to see the Republican party come together, and I’ve been a little bit divisive in the sense of hitting people hard,’ Trump said in an unusually relaxed and genial tone. ‘Ultimately, I would like to come together and get this thing done,’ Trump added.

And then there’s this story on the Rubio-Cruz fistfighting over who’s more soft on immigration.

There are two things at work here. Republican voters do not like it when candidates criticize other candidates; they like it when fire is focused on the people they see as their opponents: the liberal media and the Washington establishment. So when your two opponents are taking each other down in a way that is likely to turn off voters, why step on that narrative?

Let them fight it out, as Trump brilliantly — if improbably — positions himself as the unifier, as befits the front runner and, in his view, likely nominee.

Brilliant. He’s a master.

Maggie Gallagher is a senior fellow at the American Principles Project.