Why Cruz finally took on Trump and won't let up

“It’s a rare contrast to see [Trump] be compassionate in invoking 9/11,” Cruz’s campaign chairman said. “But it doesn’t address the fundamental thing that the senator raised. What that tells you is, he doesn’t want to tangle with the senator, actually, on what he’s raising. If you look at Donald Trump, he has had a pattern of insulting many different groups. But for some reason, when New Yorkers get insulted, he’s the first to cry out. I come from the South, and we say, ‘If you can’t stand the heat, get out of the kitchen.'”

“If Donald wants a fight, it probably wouldn’t be advisable of him to take us on in Iowa,” Sweet added.

Cruz has a lot riding on Iowa. But he’s not running a one-state campaign. He’s well organized in all four early primary states, plus the Southern and Midwestern states that dominate the calendar in March. Engaging with Trump now, as voters begin to pay more attention and solidify their choices, is meant to eliminate others —besides the New Yorker — that could stand in his way beyond Iowa.