President Trump’s order to resume nuclear weapons testing after a 33-year break comes as a new Cold War outlook grips Russia’s neighbors. From Japan to Norway, probing by Russian war jets and drones is provoking a harder line by America’s allies.

“Russia conducts daily military operations around our country while invading Ukraine, this is the reality,” Japan’s new defense minister, Shinjiro Koizumi, posted on X shortly after Japan scrambled jets to monitor two Russian nuclear-capable bombers flying along the edge of Japanese airspace. On Tuesday, Mr. Trump visited a United States Navy base near Tokyo with Japan’s new conservative prime minister, Sanae Takaichi. He announced the sale of late-generation missiles for Japan’s F-35 jets.

Mr. Trump’s order to resume nuclear bomb testing was made minutes before he met in South Korea with the Communist Chinese leader, Xi Jinping. However, the post also seemed to be aimed at Russia. In the previous week, Russia boasted of testing a nuclear-powered missile and a nuclear-powered torpedo. These announcements ratcheted up tensions in Europe, where language — and actions — are becoming less and less diplomatic.

“Putin knows: ‘If I use nuclear weapons, they [NATO] will wipe Moscow off the map’” Belgium’s defense minister, Theo Francken, told his country’s De Morgen newspaper in an interview posted Monday. The reporter had asked him how Belgium would react if Russia fired a missile at Brussels.

In the Baltics, Lithuania announced yesterday that it was closing for one month all land crossings with Belarus, the Russian satellite nation. The decision came after helium balloons drifted yesterday into Lithuania from Belarus, the fourth such incident in a week. Part of a state-sponsored cigarette smuggling operation, the balloons regularly force authorities to close the country’s main airport, at Vilnius, only 20 miles west of Belarus.

Lithuania’s president, Gitanas Nausėda, yesterday called the balloon launches “a deliberate act aimed at destabilizing Lithuania” and organized by Belarus’ secret police, the KGB.  Lithuania’s foreign minister, Kestutis Budrys, called the balloons and airspace violations “calculated provocations designed to destabilize, distract (and) test NATO’s resolve.”

Out of solidarity, Polish authorities announced yesterday that they will delay reopening Polish land crossings with Belarus. These road crossings initially were closed in response to a large, combined Belarus-Russia exercise near the border. Airports for the eastern Polish cities of Lublin and Radom were closed yesterday due to a barrage of 700 drones and missiles that Russia fired at targets across Ukraine.

Poland’s air force increasingly has its hands full protecting Polish airspace from war jets flying out of its eastern neighbor, Russia’s exclave of Kaliningrad. Yesterday, for the second time in two days, Polish jets monitored a Russian Il-20 surveillance plane as it flew over the Baltic Sea with its transponder turned off and without filing a flight plan. In three separate incidents over the last month, war jets from Germany, Norway, and Sweden scrambled to monitor Russian Il-20s as they flew without flight plans.

After Russian war planes strayed into Lithuanian airspace,  Lithuania’s prime minister, Inga Ruginiene, wrote on Facebook: “This incident once again shows that Russia is behaving like a terrorist state, disregarding international law and the security of neighbouring countries.”

After a series of drones forced the temporary closing of airports in Denmark and Germany, the European Commission drew up plans to build a “Drone Wall.” Running up and down Russia’s Western border, this “wall” is to use layers of defense to identify and block Russian drones. The wall is being built with advice from experts from Ukraine, the most experienced drone fighters in the West.

“We will intercept and shoot them down,” Estonia’s foreign minister, Margus Tsahkna, said yesterday. Last month, three Russian MiG-31 fighter jets flew through Estonian airspace for 12 minutes until they were escorted out of the area by Italian F-35s.

While the Russians play an aerial cat and mouse  game, NATO nations are preparing to act. On Monday, the British defense secretary, John Healey, unveiled in Parliament plans to allow British forces to shoot down drones over British bases. Last year, unidentified drones flew over four British airbases used by American forces.

According to a Der Spiegel analysis of drones that flew over northern Germany last month, the long parallel flight paths indicate espionage, not a weekend hobbyist.

On the ground, the post-Cold War days are long gone when war games in Europe involved generic teams with fictitious names. 

In coming days, the European Commission is to unveil a plan designed to speed tanks and heavy artillery to east from west. Aimed at rushing armaments to a front with Russia, the plan will slash customs procedures and establish routes with reinforced bridges.

The spirit of the times was captured by the warning yesterday by the Polish defense minister, Wladyslaw Kosiniak-Kamysz, about airspace incursions: “This shows that vigilance is required at all times, that Russia is in no way calming down or retreating.”

Chancellor Friedrich Merz sounds a similar note. “The threat is real. You read it in the newspapers, you hear it in the news: drone flights, espionage,” he says. “We are not at war, but we are no longer at peace, either.”