On his first visit to Asia, President Trump has oscillated between competing visions for handling the crisis with North Korea. In the run-up to the trip, he mocked diplomatic efforts as a “waste of time” and threatened to “totally destroy” the nation. On Sunday, at Yokota Air Base, in Japan, Trump, wearing a bomber jacket and surrounded by U.S. troops, hailed “America’s warriors” and said, “No one—no dictator, no regime, and no nation—should underestimate, ever, American resolve. Every once in a while, in the past, they underestimated us. It was not pleasant for them, was it?”

But, on Tuesday, in Seoul, three dozen miles from the North Korean border, Trump changed course and praised the power of negotiations. “I really believe it makes sense for North Korea to come to the table and make a deal that is good for the people of North Korea and people of the world,” he said. That posture was a diplomatic gesture to Trump’s hosts in Seoul; according to Scott Snyder, of the Council on Foreign Relations, the South Korean government signalled that it “desperately wants him to avoid baiting Kim Jong Un, stay on script, and seek a peaceful end to confrontation with North Korea.” By Wednesday, however, Trump had settled on a third mode, confrontational but controlled, delivering a speech at the National Assembly, in Seoul, that contained what he called a “direct” warning to Kim. “The weapons you are acquiring are not making you safer; they are putting your regime in grave danger,” he said. “Do not try us.” Lambasting North Korea’s economic weakness and pattern of human-rights abuses, he said, “North Korea is not the paradise your grandfather envisioned. It is a hell that no person deserves.”

After tacking briefly toward a softer tone, Trump’s speech reinforced the course that he has set—a strategic momentum that, left unchanged, stands a growing chance of leading to war. John Brennan, the former director of the C.I.A., recently estimated the odds of this chance becoming a reality at between twenty and twenty-five per cent. Richard Haass, the president of the Council on Foreign Relations, assesses the risk as closer to fifty per cent. In the Times, on Sunday, Nicholas Kristof noted these estimates and observed, “Yet we’re complacent: Neither the public nor the financial markets appreciate how high the risk is of a war, and how devastating one could be.”

Chalk it up to Trump fatigue or North Korea fatigue, or a combination of the two, but members of America’s political class—the “blob” of government officials, donors, and media types—have started to talk about war with Pyongyang as an increasingly likely prospect. Last week, I spoke to a former Cabinet secretary, a Democrat, who told me that if he were in the government today he would support attacking North Korea, in order to prevent it from launching a strike on America. This was not a vox-pop interview at the mall with a casual news consumer; it was a conversation with a seasoned American official who is inexpert on Asia but otherwise well informed and influential. It was a worrisome indicator not because the former secretary is privy to secret information—by his account, he is not—but, rather, because it reflects an emerging bout of groupthink that needs to be checked.

In another measure of the mood, the retired Admiral Dennis Blair, a former director of national intelligence who led the U.S. forces in the Pacific, wrote this week that if North Korea tests a nuclear missile in the Pacific Ocean, or conducts a nuclear test in the atmosphere—as it has threatened to do—the United States and its allies should launch a “massive . . . air and missile strike against all known DPRK nuclear test facilities and missile launching and support facilities.” In Washington, some analysts say that the White House is considering a version of that plan, betting that it would not escalate to an all-out war. Driving much of this discussion is the White House’s fundamental analytical position, which was summed in a briefing to reporters in Tokyo by a senior White House official, who said, “North Korea’s goal is not to simply acquire these horrific weapons to maintain the status quo . . . They are seeking these weapons to change the status quo. Their primary goal is to reunify the Korean Peninsula and these weapons are part of the plan.”

This belief—that if North Korea is allowed to retain its nuclear arsenal, it will seek to gain control of South Korea—has become an essential part of the White House’s thinking about the crisis, and it narrows its options, leaving the President and his advisers wary of any negotiation that might allow North Korea to retain some or all of its nuclear weapons. But the idea that North Korea’s “primary goal” is reunification is controversial. Some analysts believe that the regime’s goal may be more modest—merely its own survival—and that overstating its ambitions (and understating the potential value of a negotiated solution) is a mistake. In that telling, the White House runs the risk of reënacting the George W. Bush Administration’s march toward war in Iraq, when officials and pundits took to saying that war was not a choice but a grim necessity. To borrow a loaded phrase, some in Washington are edging toward the belief, so common in 2002 and early 2003, that it’s a matter of a preventive war now or a larger war later.

Faced with that kind of choice, there is a temptation to think that, by attacking first, America could more easily define the scope and the consequences. For instance, members of the Administration talk about their willingness to strike a North Korean missile out of the sky, during a test flight, or about the prospect of attacking a launch facility. But those scenarios rest on a fragile assumption that North Korea will not escalate the dispute by attacking South Korea or Japan in retaliation. Last weekend, in a valuable addition to the discussion, the Pentagon published a stark report that should dampen some of these imaginings. Replying to a query from Congress, Rear Admiral Michael J. Dumont, the vice-director of the Joint Chiefs of Staff, wrote, “There are no good military options for North Korea. Invading North Korea could result in a catastrophic loss of lives for U.S. troops and U.S. civilians in South Korea.” Dumont continued, “It could kill millions of South Koreans and put troops and civilians in Guam and Japan at risk.”

Another option that is frequently discussed in Washington these days is the prospect of covert action—some type of C.I.A. or special-operations program to undermine the leadership, or the use of cyber-sabotage to squelch the nuclear program. The cinematic prospects are tempting, but real-life spies warn against thinking that their profession can bring this crisis to a swift conclusion. As Michael Morell, a former acting director of the C.I.A., told me, “From my perspective, I can’t think of a covert action that would work in the case of North Korea.”

Morell said that the current conditions put pressure on the intelligence community to come up with solutions, and that is a risky scenario. “There is a long history to covert action, whereby diplomacy has not worked, military action is too risky, and so a President turns to covert action in an effort to feel like he is doing something on a wickedly hard problem,” he said. “And many White Houses end up intentionally leaking the covert action to show the American people that they are working the problem. The problem is that typically—not always, but typically—there is no way that the covert action will be able to deliver on a President’s policy objective, in this case prevent North Korea from developing the capability of putting a U.S. city at risk of nuclear attack. It takes a strong, objective [C.I.A.] director to say, ‘Mr. President, we can do that, but what you really need to know is that the chances of success are minimal at best.’ ”

The Trump Administration has succeeded more than most observers expected in pushing China to squeeze North Korea, through the use of sanctions and financial restrictions. Trump arrived in Beijing today, and he is likely to unveil more progress on that front. That strategy deserves more time to bear fruit. The alternative to war is diplomacy and pressure, and, at the moment, that option is urgently in need of a stronger lobby in Washington.