To Donald Trump, there is no American problem that bravado cannot solve.

Except maybe one.

Want to dismantle the 14th Amendment? Armed only with fire-breathing bluster, Trump will git 'er done.

Want 6 percent economic growth? Trump will make it happen.

Want to bring home thousands of jobs long ago outsourced to China and Mexico? Trump will show our trading partners and greedy U.S. multinationals who's boss.

Want to defy the laws of arithmetic, causing a $10 trillion budget hole to disappear? Trump can will it so, using only his mind.

Want to round up 11 million undocumented workers, mass-deport them, then expediently let the "good ones" back in, all on the cheap? Call in your favorite negotiator.

Same with a "big, beautiful" wall on the southern border, and health care for all, and tax cuts for all, and everything else the generous Tax Cut Santa and Spending Santa can devise, all without nicking federal budgets.

Trump once compared himself to Batman, but in truth he more closely resembles the Man of Steel. And he knows it.

A week ago, CNBC's John Harwood said to Trump, "Your answer to policy questions, how do you pay for this, how are you going to do that, is: 'I'm Trump. I'm good. I'm the best. I will get it done.' Who's your model? We don't have Superman presidents."

The Republican front-runner replied: "No, but we will if you have Trump." Thus spake Zarathustra.

A few days earlier, Scott Pelley of "60 Minutes" told Trump, "You know, the problem with a lot of these ideas is that the president of the United States is not the CEO of America. ... The Constitution is going to tell you no."

Trump's response? "We'll see."

A Trump presidency would be an all-powerful presidency, one unconstrained by ideological adversaries, other sovereign nations, constitutional restrictions, political correctness or special interests. It offers the kind of seductive tyrannical flourishes that right-wingers see in President Obama, even though Obama's legislative agenda, executive branch appointees and judicial nominees have been blocked at every turn. President Trump has made it clear he would never tolerate such bullying.

Except, it seems, when it comes to one particular issue: gun violence. On this issue, and this issue alone, Trump is — like every other Republican contender — strangely passive.

On "Meet the Press" last Sunday, Trump explained that there was no sense in even tinkering with our gun laws. "You know, no matter what you do, guns, no guns, it doesn't matter. You have people that are mentally ill. And they're gonna come through the cracks," he told Chuck Todd.

His comments on "This Week" were similarly fatalistic. "No matter what you do, you will have problems and that's the way the world goes."

When host George Stephanopoulos noted how uncharacteristically can't-do this attitude was for Trump, the latter insisted: "Now, George, I could say, oh, we're going to do this and that and it's never going to happen again. You have sick people in this country and throughout the world, and you're always going to have difficulty."

Taking a page out of the National Rifle Association's playbook, Trump then laid responsibility for gun violence at the feet of the mentally ill. But he abstained even from advocating for more screening and services for mental illness.

In other words, Trump, like other conservative politicians he claims to disdain, shrugged. Trump, a man who prides himself on his great willingness to speak the politically incorrect truth, dared not offend his base. Trump, who considers himself unrestrained by special interests, paid obeisance to perhaps the most powerful special interest in the country, the gun lobby (from which he seems to have cribbed his own gun policy proposals). Trump, the self-proclaimed strongman, is now mysteriously impotent.

This is a shame. Unlike economic stagnation, outsourcing or inconvenient budgetary arithmetic, gun violence could be addressed by concrete, workable policy solutions. All that's required is some Trumpian political backbone.

We know what could be done to at least reduce would-be murderers' access to deadly weapons, including universal background checks and closure of the so-called Charleston loophole, which allowed Dylan Roof to purchase a gun when he should have been denied one. We could also limit the size of magazines, or reinstate the assault weapons ban. Or create a federally financed gun buyback program, as proved successful in Australia. When it comes to curbing gun violence, the United States suffers not from a failure of imagination; we have a failure of will.

Where is Superman when we need him?