The lesson from Donald Trump’s dealings with North Korea and China is uncomfortable for Europe: A hard line can reduce the risk of war – sometimes.

What if Donald Trump were right for a change? Not everything has to be wrong just because he does it. And because he is trying for one time a different strategy than his predecessor. Conversely, his questionable deeds are not generally excusable if and when he has success in an isolated case.

Kim Postpones Planned Attack

It raised a storm of outrage when he threatened North Korea with destruction by means of a nuclear attack. Barack Obama would never have done that. Of course, Kim Jong Un had sworn apocalypse first. He would turn the U.S. into a “sea of fire.” Does the civilized world need to put up with that? Trump answered with “fire and fury,” and raised the ante when Kim didn’t back down right away. Then Kim softened his tone: He has postponed his attack on the U.S. base on Guam in the West Pacific.

It is irresponsible to threaten nuclear war. However, one must admit: Trump was successful. So he will confidently ignore demands from Russia and China to cancel the yearly U.S. – South Korean maneuvers this week for the sake of peace.

China Finally Wants to Implement Sanctions

The same is true of threats of trade sanctions. Trump says that China must exert more pressure on North Korea. China handles more than 90 percent of North Korea’s imports and exports. Trump wants to force North Korea into a treaty patterned on the nuclear deal with Iran: Pyongyang should stop the development of nuclear missiles, and this would be internationally monitored. In a counter measure, all of Korea would be nuclear-free and the U.S. would decrease its military presence in South Korea.

Here, too, Trump had success after some back and forth. In the past year, Russia and China had increased their trade with North Korea in spite of the U.N. sanctions. Now China is making a serious effort to hinder the smuggling of forbidden goods. Experts say North Korea cannot build the intercontinental missiles by themselves. The propulsion units would come from Russia, China or perhaps from Ukraine. With watertight sanctions, Kim would get no nuclear missiles. In the case that Trump’s trade conflicts with Beijing and Moscow* were to succeed, the threat of war would decrease.

The Mild Approach Doesn’t Even Reliably Work in Europe

It is an uncomfortable experience for Europe: Harsh threats can save the peace. It depends on the individual case. Many in this part of the world believe the opposite: The military is dangerous. Whoever answers the arms build-up of his neighbor with an arms build-up of his own as a deterrent is a warmonger. Even the threat of trade wars is irresponsible; the ordinary people always suffer. Conflicts must be brought to peace by diplomacy. Escalation is wrong.

At the same time, this conceptual approach doesn’t even reliably work in the EU. Here, too, nations emphatically defend their own interests. Look at Poland and Hungary. Look at the euro and migration crises. How, then, can one expect a dictator to be influenced by diplomatic efforts alone? In most countries on earth, threats are an accepted method of politics.

Putin, Erdogan and Kim Unscrupulously Employ Pressure and the Military

Putin, Erdogan, and Kim unscrupulously employ pressure and the military; Trump does so as well. In addition, the West has had success with threats. John F. Kennedy remained tough in the Cuba crisis; the Soviet ships with missiles turned around. The upgrading of NATO led to the dismantling of Soviet missiles. The advance of pro-Russian militias in eastern Ukraine ended when Chancellor Merkel assured Putin in Minsk that otherwise the West would deliver weapons to Ukraine. Since Trump bombed Syrian airports, no more chemical weapons deployments have been known.

Threats and toughness are not always right. Used too excessively, they lose their effect. They must be believable. Therein lies the problem with Trump. He appears to be a player who likes to bluff. That can end fatally.

*Translator’s note: This trade conflict refers to Trump’s attempts to get Beijing and Moscow to abide by the U.N. sanctions against North Korea.