As Donald Trump stumbles in his bid for the Republican presidential nomination, one group has been sorely disappointed by his belated display of weakness: Democratic operatives, who had been hoping fondly to run against him in November.

Democrats’ delight at the prospect of a Trump candidacy is well-founded. Last week’s Post-ABC News poll finds that an impressive 67 percent of Americans have an unfavorable view of Trump and only 31 percent have a positive view — far worse than Ted Cruz (36 percent positive, 53 percent negative), or Hillary Clinton.

All signs suggest Trump would be an electoral disaster for Republicans, but I won’t join those who for that reason want him to be the Republican nominee. The important thing is not what’s best for Democrats but what’s best for the country — and that means not having a race-baiting demagogue as the nominee of a major party.

I’m no Cruz booster. I’ve called him, at various points, a modern-day McCarthy and a prolific fabulist who isn’t above using an anti-Semitic dog whistle when he condemns “New York values.” Many of Cruz’s policies — on gay rights, health care and Social Security, for example — are more objectionable than Trump’s.

But Trump isn’t dangerous because he’s conservative. He’s dangerous because he seems willing to govern outside our constitutional system, with his talk of torturing prisoners and targeting innocent civilians, with his winking at violence at his events and his plans to block entry to the United States on the basis of religion.

On his home turf April 14, Republican presidential candidate Donald Trump revved up supporters, calling rival Ted Cruz, "Lying Ted." Polls showed Trump with a commanding lead in the GOP race in New York, scheduled for April 19. (Reuters)

Clinton is well positioned to beat either man, but even if Trump is easier to defeat, his nomination alone would be a blow to U.S. standing, which has already suffered from his success. British Prime Minister David Cameron, who called Trump’s proposed ban on Muslims “divisive, stupid and wrong,” said of Trump: “If he came to visit our country, I think he would unite us all against him.”

Cruz, in the Senate and in his campaigns, has embraced the most extreme conservative views. But I met Cruz 16 years ago (before his self-reinvention as a tea party guy), and I’ve spoken with many of his friends and acquaintances from college and law school. This has all led to one conclusion: Cruz, though undoubtedly conservative, is above all ambitious. And in service of that overriding ambition, he is perfectly happy to be a phony.

Doubt his phoniness? In an interview last week with Hamodia, a Jewish newspaper, he declared that “one seminal event that impacted me as a child was the Entebbe raid,” in which Israeli commandos freed hostages of an airplane hijacking. “What the Entebbe raid said to me was, if you’re a terrorist, you may capture an Israeli. . . . But you are going to die.” That struck Cruz as “a very Texan approach.”

The raid that spurred such deep thoughts about the Jewish state and the Lone Star State was in 1976 — when Cruz was 5 years old and not long after his family moved from Canada.

On the stump, Cruz talks about how Jimmy Carter supposedly “endorsed” Trump by saying Trump is “malleable” and Cruz is “not malleable.” But Cruz is malleable, in one way: He won’t let ideology get in the way of his ambition. (His straddle on the Senate immigration bill was artful, positioning himself to say he was for it if it succeeded but against it if it didn’t.) If he were to become president, his all-consuming ambition would drive him to succeed, which would mean jettisoning unpopular proposals. Cruz believes in Cruz — not in the tea party agenda he opportunistically rode to power.

Finally, unlike Trump, Cruz is a creature of democratic institutions. We see this now in the way he has, through his mastery of convention rules and his outreach to party insiders, outmaneuvered Trump in lining up commitments from delegates in Cleveland. It was always thus, going back to his days running for student government at Princeton and as a mid-level staffer aggressively climbing his way through George W. Bush’s presidential campaign.

Trump has talked blithely about ordering the military to do illegal things; his bravado suggests he’s not inclined to let small things such as the separation of powers get in his way. He concurred with a supporter’s labeling of Cruz as a “pussy” for being insufficiently committed to torture. And Cruz hasn’t joined Trump’s lawless call for killing the non-combatant relatives of terrorists: “We’ve never targeted innocent civilians, and we’re not going to start now.”

This is why Cruz is less dangerous than Trump. Cruz is often dishonest, and he takes extreme and sometimes appalling positions. But he has shown an inclination to play by the rules — and that’s a safeguard Trump doesn’t offer.

Twitter: @Milbank

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