Republican Presidential candidate Donald Trump. (Tom Lynn/Getty Images)

Whatever else one may think about Donald Trump, he has a gift for labeling opponents.

Jeb Bush? “Low energy.”

Ted Cruz? “Lyin’ Ted.” (Trump directs supporters to drop the “g.”)

Marco Rubio? “Liddle Marco.” (He decrees that little be spelled with a double “d.”)

“You have to brand people a certain way when they’re your opponent,” Trump said at a campaign rally recently.

He’s right. So how about a brand for Trump? I suggest “Dangerous Donald.”

This label has the virtue of being supported by many of Trump’s fellow Republicans. “I don’t know anyone who would be comfortable with someone who behaves this way having his finger on the button,” remarked Cruz, his GOP rival, echoing a common complaint of many Republicans. “I mean, we’re liable to wake up one morning and Donald, if he were president, would have nuked Denmark.”

There are many other labels that could be applied to Trump: sexist: Bigot. Xenophobe. Con man. Bully. Authoritarian. Flip-flopper. Ignoramus. An entitled rich kid turned oft-failed businessman.

But “dangerous” ties them all in, because it gets at the recklessness that most concerns people about Trump: His loose talk about using nuclear weapons and starting trade wars. The violence at his events. His put-downs of women, immigrants and racial minorities. His threat to order the military to break laws by torturing and by targeting innocents. His capricious call to ban Muslims from entering America. His profanity on the stump.

Trump is accustomed to steamrolling bankers, employees and reality-show contestants alike. But what explosion might result if this unpredictable man were president and world leaders, or Congress, told him “No”?

Each day brings more data points to support the “Dangerous Donald” branding. In a forum Wednesday hosted by MSNBC’s Chris Matthews, Trump said that “there has to be some form of punishment” for women who have abortions if the procedure is outlawed. (He backed down after an outcry.) On Tuesday, a 15-year-old girl protesting Trump in Wisconsin was hit in the face with pepper spray by a Trump supporter.

Also Tuesday, Trump campaign manager Corey Lewandowski was charged with battery in Florida for roughing up a female reporter at a Trump event, the second time Lewandowski was in a filmed altercation. Lewandowski had denied touching the reporter before video footage emerged — and Trump defended Lewandowski by saying the reporter’s pen could have been “a little bomb” or a knife.

Democrats are just beginning to test their strategies for Trump, but a new poll by the Democratic group Democracy Corps finds that the “dangerous” attack is persuasive. The survey, done for the Women’s Voices Women Vote Action Fund, found that 58 percent of likely voters nationally have serious or very serious doubts about Trump when they read this statement:

“Donald Trump says he gets his national security advice from TV shows and says attending a military academy in high school counts as experience. National security is serious business, and nothing is more dangerous than an erratic strongman who can send your children to war or fire a nuclear weapon.”

This attack was second only to a statement highlighting Trump’s sexism (66 percent had serious or very serious doubts) and ahead of attack lines describing him as xenophobic (53 percent) and an egomaniac (42 percent) — and “Dangerous Donald” has the potential to incorporate the other three attacks on Trump.

The Dangerous Donald attack would have some echoes of Lyndon Johnson’s immortal Daisy ad, identifying Barry Goldwater with a mushroom cloud. Trump practically narrates such an ad himself.

He says he wouldn’t rule out using tactical nuclear weapons against the Islamic State and promises to “bomb the sh-- out of” the terrorist group. He has alternated between saying he would rescind the Iran nuclear deal and saying he would enforce it vigorously. He has toyed with the notion of bombing Iran and talks up a 45 percent tariff on Chinese goods.

He has described his strategy toward the Islamic State as “shoot first and talk later.” He has said it might be okay for Saudi Arabia, Japan and South Korea to have nuclear weapons. His talk of a Muslim ban was labeled “divisive, stupid and wrong” by British Prime Minister David Cameron, one of many alarmed allies.

Trump said he knows “more about ISIS than the generals do” and is his own best adviser on foreign affairs “because I have a very good brain.” Asked by NBC’s Chuck Todd where he gets his military advice, he said, “I watch the shows.” He told a biographer he “always felt that I was in the military” because he attended a military-style prep school.

And he praises the virtues of an unspoken military strategy that keeps the world guessing. To Fox News’s Bill O’Reilly, he said, “The voters want to see unpredictability.”

Do they? Dangerous Donald will find out.

Twitter: @Milbank

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