Max Boot

Opinion columnist

While the rest of America tried to take it easy over Labor Day weekend, President Trump was working overtime raising blood-curdling possibilities. He mulled withdrawal from the U.S.-South Korea Free Trade Agreement. He threatened to stop all trade "with any country doing business with North Korea.” He considered how to end the Deferred Action for Childhood Arrivals (DACA) program, which could result in the deportation of 800,000 undocumented immigrants brought to the United States by their parents.

If Trump is serious, each of these decisions would be a disaster.

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Pulling out of the Free Trade Agreement with South Korea would lead to divisions between Seoul and Washington at a time when it is imperative that they remain unified against the growing North Korea threat. Ending all trade with any country doing business with North Korea would mean ending all trade with China, America’s largest trading partner; two-way trade between the U.S. and China is worth an estimated $650 billion, and cutting off trade ties would cripple U.S. companies such as Apple that rely on Chinese supply-chains. Deporting immigrants who came here as children would be a moral and economic catastrophe that would result in the expulsion of people who did nothing wrong and have become productive members of our society.

But of course there is good reason to doubt that Trump is serious about any of this — even about ending DACA, which he may want Congress to save because on Tuesday he gave them a six-month window and tweeted “do your job — DACA!” The president is a notorious BS artist who has reached the White House by taking a right turn on the Boulevard of Broken Promises, with frequent detours onto the Avenue of Empty Threats.

Just in the course of running for president, he threatened to sue at least 20 entities or individuals, including The New York Times and The Washington Post and the women who accused him of sexual assault. He even threatened to revise the libel laws to make such suits easier to win. Previously he threatened to sue the producers of “Sharknado 3” for not casting him as the fictional president. And he has a long history of threatening to sue people who question his (probably inflated) net worth. Sometimes he has actually gone to court, but most often he has prudently refrained from making good on his threats.

His hyperbolic habits carried over to the presidential race. As documented by Politifact and AOL, his empty promises (so far) include saving the coal industry, making Mexico pay for a border wall, refusing to take a vacation as president, repealing Obamacare, ending all immigration from Muslim countries, bringing back waterboarding, building a safe zone for Syrian refugees, renegotiating the Iran nuclear deal, moving the U.S. embassy from Tel Aviv to Jerusalem, and labeling China a currency manipulator.

A few of these objectives — principally the repeal of Obamacare and a ban on entrants from Muslim countries — he actually tried to achieve. Most of the others he simply ignored or negotiated away. For instance, he said he would not label China a currency manipulator in return for its help in reining in North Korea (which hasn’t been forthcoming). On the border wall with Mexico, he has gone from promising to make Mexico pay for it to promising to make Congress pay for it, by threatening a government shutdown if necessary — another threat that in all likelihood will turn out to be just hot air.

Trump has already gotten into big trouble by bluffing. Remember when he tweeted that former FBI Director James Comey better hope there were “no 'tapes'” of their conversations? Trump hoped that this threat would intimidate and silence the former FBI director. Instead it led Comey to call Trump a liar under oath, and set in motion a train of events that led to the appointment of a special counsel whose investigation threatens to consume the Trump presidency.

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Trump's threats of military action are even more dangerous. His claim that there is a “military option” for Venezuela has undermined American attempts to isolate the Maduro dictatorship. His threats to North Korea, meanwhile, raise the risk of war. Back in January, confronting the threat of North Korea acquiring an ICBM, Trump vowed, “It won’t happen!” Now that North Korea appears to have an ICBM, Trump told reporters on Aug. 8: “North Korea best not make any more threats to the United States. They will be met with fire and fury like the world has never seen.” North Korean threats have continued, along with missile and nuclear tests, and no “fire and fury” has yet rained down on Pyongyang.

Braggadocio may be fine, even useful, for a TV host or real-estate mogul, but it’s dangerous for a president. All deterrence is based on the presumption that a president’s promises must be taken seriously. There is always an element of bluff involved: Would the U.S. really have traded Washington for Berlin during the Cold War? Would it trade Seattle for Seoul today? That’s why it is so important to have a president whose words carry weight.

Instead we have a president whose bluffs have been called time and again. If Trump makes good on any of his threats, it will be a huge surprise. This kind of unpredictability is destabilizing. If you were looking for a formula for blundering into war, this would be it.

Max Boot, a member of USA TODAY’s Board of Contributors, is a senior fellow at the Council on Foreign Relations. Follow him on Twitter: @MaxBoot.