Donald Trump needs help. The wheels have been coming off his presidency since he took the oath of office, and he's rapidly becoming his own worst nightmare: a weak, ineffectual laughingstock. Trump goes through subordinates faster than Katy Perry changes outfits, and at this point only a knave, a fool, or a desperate patriot (see: John Kelly) would want to work under the disrupter-in-chief.

It is also abundantly clear that Trump is unfit for the office of president, as senior GOP officials warned during the campaign. He lacks the training or the temperament for the job and he has a tin ear when it comes to picking advisers. If he had a scintilla of self-awareness, he would know he's become the sort of loser he's always denigrated (and may have always suspected he really was, deep down).

The temptation to see Trump's comeuppance as an opportunity for some schadenfreude should be resisted, however, because the stakes are just too great. Those who care about the United States and the world can take no pleasure in the damage Trump & Co. have already done.

There was his bewildering decision to exit the Trans-Pacific Partnership, and the head-in-the-sand denialism that led him to pull the U.S. out of the Paris climate accord. There is the willful and ongoing destruction of the State Department, an incomprehensible blunder that will cripple the United States' international influence for years to come. And then there's his peculiar fondness for authoritarian leaders, his susceptibility to whatever self-serving blandishments they offer his vulnerable ego, and his refusal to take responsibility for just about anything. In Trump's Oval Office, the buck always stops somewhere else.

But I'm not here to dish more criticism; I'm here to help. As bad as Trump's first six months have been, there are a number of major foreign-policy blunders he hasn't made yet and for which we should therefore be grateful. Unfortunately, there are also signs he's contemplating several of them, and plunging ahead may look more tempting as his political fortunes erode. The more desperate he gets, the more he may be inclined to divert attention from his incompetence here at home by stirring up trouble somewhere else.

As a public service, therefore, I offer here my top five foreign-policy blunders Trump hasn't made yet (but still might).

1) War with North Korea.

Dealing with North Korea's nuclear arsenal and missile development program is a real challenge, and there's no clear and obvious step that would make it go away. Thus far, however, Trump's approach has been ignorant, impulsive and counterproductive. First he declared he'd never let North Korea test another ICBM, tweeting in January "It won't happen!" Well, I guess we can consider that bluff called. Despite the quick tutorial he received at Mar-a-Lago from Chinese President Xi Jinping, he's continued to blame China for not "solving" this issue, as if he still expects Beijing to sacrifice its own interests in order to gratify ours. Trump has also mishandled relations with South Korea, making bellicose statements on trade, demanding that Seoul pay for the THAAD deployment we had previously negotiated, and giving new South Korea President Moon Jae-in even more reason to be skeptical about the whole U.S.-South Korean alliance.

Here's the problem: The U.S. could in theory launch airstrikes against North Korea's launch facilities, thereby delaying the development of an ICBM that could reliably reach the U.S. But Pyongyang is unlikely to absorb a U.S. attack and do nothing in response. The worse case, of course, is a rapid escalation to all-out war, which could leave the South Korean capital of Seoul in ruins and might even drag China into the fray. But even if North Korea didn't escalate that much, Kim Jong Un would almost certainly try to inflict significant costs of some kind on South Korea, if only to drive home the lesson that the U.S. was all-too-willing to sacrifice South Korean lives today in order to ward off a hypothetical danger to Americans tomorrow. It's hard to think of any development that would be more likely to sever the U.S.-South Korean alliance, thereby undermining the U.S. position in Asia even more. And if you were Xi Jinping and hoping to drive the U.S. out of Asia altogether, such a development would be most gratifying indeed.

The good news is that the U.S. and its allies have a familiar alternative: deterrence. It would obviously be better if North Korea did not have nuclear weapons or long-range missiles, but deterrence worked against Stalin, Khrushchev, Brezhnev, Mao, and a number of other supposedly "irrational" and brutal leaders. The U.S. has thousands of nuclear weapons, and it has shown a clear willingness to strike back hard when its territory is attacked. Look at how it responded after Pearl Harbor and 9/11. There's no reason to think Kim Jong Un is suicidal — on the contrary, self-preservation seems to be his top priority — and firing a nuclear bomb at the U.S. (or even one of its allies) is the best way to guarantee his own prompt demise.

To repeat: North Korea is a vexing problem with no ideal answers, but going to war would make a bad situation worse.

2) Destroying the nuclear deal with Iran.

During the 2016 campaign, Trump repeatedly referred to the Joint Comprehensive Plan of Action (JCPOA) with Iran as a "disaster" and the "worst deal ever negotiated." He's continued to rail against it ever since, abetted by the usual suspects at AIPAC, the Foundation for Defense of Democracies, and self-interested allies like Israel and Saudi Arabia. (The willingness of Congress to go along with additional sanctions — in an obvious bow to our old friend the Israel lobby — hasn't helped). Trump has grudgingly acknowledged Iran is in fact abiding by the deal but he still seems eager to find some way to blow it up, even in the face of united opposition from his top national security advisers.

To paraphrase Talleyrand, this step would be worse than a crime, it would be a blunder. The other signatories to the JCPOA won't go along with the U.S., which means there's no chance of reimposing the stiff global sanctions that helped persuade Iran to sign the deal in the first place. (Sanctions would "snap back" if Iran did violate the deal, but not if Washington reneges.) European, Russian and Chinese companies will make lots of money trading and investing with Iran while U.S. firms are shut out, and China's influence in the region will likely grow. Iran's hard-liners will be strengthened, and all the more so if the U.S. tries to get back into the foolish business of "regime change." Indeed, there's no better way to put Iran back on the road to an actual nuclear weapon than to start dangling that particular possibility again.

What Trump may not understand is that this step will eventually leave the U.S. with only two realistic options: 1) acquiescing to an Iranian bomb or 2) launching a preventive war. (Fantasists continue to dangle "peaceful" regime change in Iran as some sort of third option, but this is wholly unlikely and is used merely to justify additional sanctions and thwart intelligence efforts to resolve our differences with Tehran.)

My concern, of course, is that Trump might conclude that a quick Middle East war would provide a temporary distraction from the Russia investigation, the chaos in the White House, and his stillborn legislative agenda. He might even convince himself that this would be a decisive act of leadership that would bolster his approval ratings the same way his cruise missile strikes on Syria did. He's wrong: Sowing more carnage in the region is hardly in America's interest and any boost he might get in approval will dissipate quickly. Has everyone forgotten how well our little adventures in Iraq, Libya, Yemen, Somalia and Afghanistan went?

3) Starting a trade war.

Protectionism has been a key part of Trump's platform since his first involvement in politics, and loud denunciations of "bad deals" were staple ingredients of his campaign rallies. This same knee-jerk hostility to open trade also underlay his rejection of TPP and his criticisms of NAFTA and the free trade agreement with South Korea. Apart from a mostly symbolic action on softwood lumber, however, Trump has thus far refrained from imposing significant trade sanctions. Nor has he delivered on the earlier promise to "tear up" NAFTA; instead, he now says it will simply be renegotiated.

Nonetheless, there are a number big-time protectionists in key positions in the administration, and Trump has continued to hint that he would like to play hardball with the countries he (falsely) believes are "stealing American jobs." He recently said that tariffs on imported steel could be imposed "soon," a step Dan Drezner rightly termed "the trifecta of counterproductive policy measures." The world economy is doing better but is hardly in robust, good shape; a round of reciprocal, tit-for-tat trade restrictions is the last thing anybody needs right now. But can one be confident Trump won't eventually go this route, either as a result of deliberate calculation or idle whim?

4) Doubling down in Afghanistan.

Trump's most appealing position during the campaign was his unequivocal opposition to "nation-building," to include America's quixotic 16-year quest to achieve "victory" in Afghanistan. He hasn't become an enthusiastic convert to this particular folly, but his views seem to be wobbling, and he may eventually approve the military commanders' requests to send a few thousand more troops there to stave off complete defeat.

Such a decision might not be as catastrophic as letting the Iran deal lapse or bombing North Korea, but it would still be a blunder. As I've argued before, adding a few thousand more troops to the Afghan mess will cost money and lives but is unlikely to alter the ultimate outcome. Get real, folks: The U.S. is not going to determine Afghanistan's fate, whether it adds 5,000, 10,000, or 100,000 more troops or stays there five, 10, or 20 more years. Rather, the fate of that unhappy country will be determined by its own people, and to some extent by its immediate neighbors — not by a war-weary superpower from the other side of the world for whom Afghanistan's fate is hardly vital. If Trump accepts the generals' advice, he'll be making the same mistake his predecessor did.

5) Arming Ukraine.

Having mismanaged the Russia portfolio through a combination of naiveté, incompetence and the inability to tell a straight story, Trump and his intimate associates have had to reluctantly accept a new round of congressional sanctions on Russia. Instead of working things out with Putin to our mutual benefit, relations with Moscow are even worse than they would have been under Hillary Clinton (which is saying something). So now the Pentagon and State Department (or what's left of it) have reportedly recommended that the U.S. provide a boatload of new armaments to the Ukrainian government.

I've cautioned against this step in the past, and I see no reason to change my position now. The mess in Ukraine arose from a misguided effort to pull Ukraine into Western economic institutions (via the European Union accession agreement), raising legitimate fears in Russia that NATO membership was next. In a brutal but predictable move the Obama administration should have anticipated, Russia thwarted this effort by seizing Crimea and backing separatist movements in eastern Ukraine. The result has been a disaster for the Ukrainians and a blow to security in Europe.

Even so, arming Ukraine is not a good idea. Russia has no interest in trying to reincorporate Ukraine, because the last thing Putin needs is millions of unhappy Ukrainians under Moscow's rule. It does have an interest in keeping it neutral, however, and there is every reason to expect Moscow to double down if we arm Ukraine and the separatists start to lose ground. Russia is much weaker than we are, but it is also right next door and Ukraine's status matters a lot more to it than it does to us or even to most of Europe. (If you have trouble grasping that fact, just recall how quick the U.S. has been to intervene in places like Cuba, Mexico, Chile, the Dominican Republic, El Salvador and Nicaragua, whenever it didn't like political trends in these places.) The more help we send to Kiev, the more our reputation will be committed and the harder it will be to avoid the slippery slope of ever-deeper involvement.

To be sure, threatening to aid Ukraine might give Washington a bit more leverage in crafting a long-term settlement to this problem. If there was a serious negotiating effort underway, I might see this possibility as something to keep in our diplomatic tool kit. But that rationale would require having a secretary of state who took his job seriously and a president who understood the value of diplomacy. Until then, "first, do no harm" should be the rule of the day.

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Avoiding these five blunders won't rescue Trump's presidency or reverse the decline in U.S. influence he has overseen. But there are hardly any situations in life that can't get worse, and we can only cling to the possibility Trump has the good sense not to pour more gasoline on his raging dumpster fire of a presidency. I only wish there were more evidence to justify that hope.