Dutch soldiers depart from Eindhoven Airport in the Netherlands on Oct. 19. (Remko de Waal/EPA-EFE)

WARSAW — One month after Russia launched its biggest-ever military exercise with 300,000 soldiers, its main rival to the west returned the favor on Thursday. About 50,000 troops will participate in the two-week-long Trident Juncture NATO drill in and around Norway. Besides the 29 member states, troops from non-NATO countries Finland and Sweden were also invited to join.

While officials have been careful to emphasize that they are defending Norway’s sovereignty against a “fictitious aggressor,” Russia has voiced anger with the exercise. Russian Foreign Ministry spokeswoman Maria Zakharova has described the drills as “saber-rattling,” saying that “such irresponsible actions are bound to lead to a destabilization of the political situation in the North, to heighten tensions.”

NATO counters, however, that recent aggressions have mainly originated in Moscow. Russia and European Union member states have traded accusations over airspace violations and military buildups in Eastern Europe.

The exercise also comes days after President Trump announced that he would withdraw the United States from a landmark Russian-American treaty in place since the Soviet era that limits intermediate-range nuclear weapons. Both the Obama and the Trump administrations have accused Russia of violating the INF pact, despite persistent Russian denials.

Even though U.S. allies in Europe have acknowledged Russian violations, they have urged the United States to stick to the agreement, once again revealing the divisions within NATO that have deepened since Trump became president.

The Dutch marine vessel Hr. Ms. Johan de Witt is loaded with vehicles and goods in the Netherlands earlier this month. (Robin van Lonkhuijsen/EPA-EFE)

Ahead of a major NATO summit this summer, U.S. allies even feared a crackup of the alliance, after Trump repeatedly voiced doubts over defending nations he considers to be in breach of their own financial commitments. Despite the verbal attacks, those fears have so far not materialized. Trump has even supported some NATO-led efforts to strengthen the alliance.

But U.S. allies in Europe still worry that the president is not fully committed to the alliance, which is based on the principle of common defense in case of an outside attack on one of its members. In July, Trump suggested the United States may not in all cases defend tiny NATO member state Montenegro, referring to the country as a broader example rather than commenting on a specific threat. Many smaller countries in the Baltic region right next to Russia are in a similar position as Montenegro and immediately voiced complaints over Trump’s remarks.

But the United States is also by far the most powerful NATO member. In 2016, U.S. defense spending was nearly three times as much as the rest of NATO.

Despite speculation over further U.S. troops reductions in Europe, however, the United States has announced a boost in its ranks in Germany, Norway and other countries in recent months.

Up to 700 U.S. Marines will be based in Norway in the coming years, where they will cooperate with British troops who are also headed north. The moves come after Russia similarly boosted its troop presence in the north of Europe, near the Arctic.

Norway is one of four NATO countries sharing a border with Russia. With tensions running high, NATO officials emphasized this week that all elements of the current exercise would be at least 310 miles far away from the Russian border.

“There should not be any reason for the Russians to get scared or see this as anything other than a defensive exercise,” said Norwegian Lt. Gen. Rune Jakobsen.

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