A new poll makes clear: Donald Trump can win this election if he keeps hammering on the anvil. That is, hammering with the same hammer, on the same anvil, for the next five months. The anvil, of course, is the basic issue of homeland security, and the hammer is the action needed to keep the country safe.

The latest Reuters poll asks, “Agree/Disagree: The United States should temporarily stop all Muslims from entering the United States.”

Agree is 50, Disagree is 42. In other words, Trump now has the benefit of an eight-point advantage on the central question of Muslim entry into the U.S. — a question made even more central in the wake of the Orlando mass-murder.

In politics, there’s a time for creativity and poetry and spontaneity, but more often that not, politics is akin to warfare — you win by slugging it out. That is, it’s a simple question of ordnance: Which side can put more firepower toward the other side, thereby doing the most damage?

Okay, that’s a boring, to say nothing of bloody, way of looking at the situation. But the end goal, victory, is not boring. And that Reuters poll tantalizes us: If Trump can stay focused on the single issue of Muslim immigration for the next five months — do you want more Syrian refugees, and potentially more Omar Mateens, coming in the country or not? — he will not only win but win handily. That is, if — and once again, it’s necessary to stipulate the “if” — he can focus on that pressure point, he will win. The American people are with him on that key issue, and so now he must rally them to that issue. He must put the question bluntly: Which side are you? It’s that simple.

Indeed, worldwide, the dominoes of Trumpian nationalist-populism are tumbling away from the trans-national globalists. In countries as different as India, Israel, the Philippines, Russia, and Turkey, nationalist-populists are winning elections — usually in landslides. One needn’t be a fan of all those foreign leaders to recognize nonetheless the populist trend.

Meanwhile, in less than two weeks, Britons go to the polls to vote on “Brexit”; the latest surveys indicate that the English will, finally, vote their independence from the bureaucrat- and jihadi-infested European Union. That will be another epic defeat for the international bureaucrats. Finally, here at home, the Trans-Pacific Partnership, the Obama administration’s last attempt at imposing more bureaucratic corporate globalism on the American people, seems dead — and will be dead, for sure, if Trump wins.

So yes, the stakes are high.

Yet they’ve been high in the past as well, and America has come through. A century and a half ago, back in 1864, the North’s General Grant had the South’s General Robert E. Lee cornered around Spotsylvania in central Virginia. The Southerners were well entrenched, defending themselves on their own home turf.

Yet Grant planned to win, no matter what the cost, and he had the edge in men and materiel. So it was just a question of sticking to the plan and squeezing Lee like an anaconda. Or, to switch metaphors, hammering Lee on the anvil of Union steel. As Grant wrote in one of his dispatches, “I propose to fight it out on this line if it takes all summer.” And that’s what he did. Lee’s men were brave and fought well, but they were badly outnumbered. And so Grant, dogged and determined as always, played his hand to victory.

So with Ulysses S. Grant as an inspiration, maybe Donald J. Trump can do it, too.