One of the biggest questions about President Trump is how he would respond to a crisis. Thus far, his presidency has been marked by controversies and stubborn politics, yes, but also by a strong economy and no natural disasters, major domestic terrorist attacks or new large-scale foreign conflicts.

That may be starting to change. A new Washington Post report indicates that North Korea is approaching the Trump administration's red line faster than previously thought.

According to The Post's Joby Warrick, Ellen Nakashima and Anna Fifield, a previously secret Defense Intelligence Agency analysis indicates that Kim Jong Un's regime has produced a miniaturized nuclear warhead that can fit inside one of the intercontinental ballistic missiles that it has been testing. Those tests drew a unanimous vote on new sanctions from the United Nations Security Council over the weekend.

The big takeaway, as The Post is reporting, is that North Korea's nuclear capabilities appear to be advancing far more rapidly than previously believed. This is a milestone when it comes to North Korea's ability to strike distant targets with nuclear weapons. Although it's not known yet that Pyongyang can strike the United States with an ICBM, U.S. officials concluded last month that the effort was also proceeding more rapidly than experts had anticipated.

Now we find out that those ICBMs could be “nuclear-tipped.” In other words, North Korea may have solved half of the puzzle when it comes to threatening the U.S. mainland with a nuclear weapon — something it has made clear is its goal.

And importantly, that's a threshold that the Trump administration has said North Korea simply wouldn't be allowed to cross.

North Korea just stated that it is in the final stages of developing a nuclear weapon capable of reaching parts of the U.S. It won't happen! — Donald J. Trump (@realDonaldTrump) January 2, 2017

“It won't happen!” Trump tweeted in January. National security adviser H.R. McMaster also said as recently as this weekend that North Korea having nuclear weapons that could threaten the United States would be “intolerable, from the president's perspective.” The DIA report is dated July 28, more than a week before McMaster made those comments.

“The president has been very clear about it: He said he's not going to tolerate North Korea being able to threaten the United States,” McMaster told Hugh Hewitt on MSNBC.

McMaster said the list of possible responses to that “includes a military option.” As The Post's report indicates, plenty of other options also are on the table, including new multilateral negotiations and putting U.S. battlefield nuclear weapons back on the Korean Peninsula.

“Obviously, war is the most serious decision any leader has to make,” McMaster said. “And so, what can we do to make sure we exhaust our possibilities, and exhaust our other opportunities to accomplish this very clear objective of denuclearization of the peninsula, short of war?”

Trump had stern words for Pyongyang on Tuesday afternoon, following The Post's report.

"North Korea best not make any more threats to the United States; they will be met with the fire and the fury like the world has never seen," Trump said. "[Kim] has been very threatening beyond a normal state, and as I said they will be met with the fire and fury and frankly power, the likes of which this world has never seen before."

Trump's statement, notably, suggests a firm response to any more threats, which North Korea makes often. So yet again, Trump seems to be setting a red line for which he may have to answer.

The prospect of war, of course, can't help but hang over this entire drama. And polls show that Americans are increasingly resigned to the fact that the conflict may be headed in that direction. While they don't necessarily back military action now, it's clear that public support could quickly be marshaled under the right circumstances. A new Chicago Council on Global Affairs poll, for instance, shows that 62 percent of Americans would support sending troops if North Korea invades South Korea — up sharply from recent years. The poll also shows a rise in the threat North Korea is perceived to pose, with 75 percent labeling it a critical threat.

But a CBS News poll released Tuesday morning shows pessimism about Trump's ability to handle a showdown. About 6 in 10 registered voters — 61 percent — said they were “uneasy” about Trump's ability to deal with the situation. Only 35 percent said they were “confident.”

The same poll showed that only 29 percent favored military action now, but Republicans were about evenly split, with 48 percent in favor — a striking level of support for military action in the president's own party. And those numbers are likely to rise given Tuesday's news.

Trump received plaudits for his limited airstrikes against the Syrian government and even seemed dazzled by his ability to launch them. Increasingly, he also seems to be facing some difficult decisions ahead on North Korea. And for the American people, that's a moment that's clearly interlaced with fear.