“He’s a nasty guy. A very nasty guy.”

Donald Trump was talking about Ted Cruz and with the same uncanny instinct that unmanned Jeb Bush with two words (“low-energy”) he’d put his finger on Cruz’s Achilles heel.

In many ways Ted Cruz looks like the archetype of a candidate who should win a Republican Primary: A true believer. An ideologue. A true-blue Conservative who’s battled compromisers – like Mitch McConnell – in Congress.

Watching the last two Republican debates, both times, I found myself listening to Cruz and nodding and then, suddenly, for no apparent reason the bottom fell out of the bucket – I thought, I don’t want to hear him say another word. Listening to Cruz had become unpleasant. Was it his voice? His face? His eyes? Was he mean? Consumed by ambition? For some intangible reason I didn’t want to hear Ted Cruz say another word.

And now Donald Trump has laid open that wound with four cutting words: He’s a nasty guy.

And Cruz doesn’t seem able to stanch the bleeding.