With the Ukraine Invasion, NATO Is Suddenly Vulnerable

BRUSSELS — A new front line of conflict is taking shape in Europe, with enhanced levels of risk that raise questions about whether NATO will, or even can, respond effectively.

Having invaded Ukraine and deployed its troops in a compliant Belarus, Russia has suddenly extended its military power to the borders of several NATO countries, including the Baltic nations.

If Russia succeeds in taking over Ukraine and keeping bases in Belarus, as many experts now expect, its forces will extend from the borders of the Baltics and Poland to Slovakia, Hungary and northern Romania, making it significantly harder for NATO to defend its eastern flank.

And only a thin corridor some 60 miles long between Lithuania and Poland separates Russian forces in Belarus from Kaliningrad, the Russian territory on the Baltic Sea that is stuffed with missiles easily capable of flinging conventional or nuclear warheads into the heart of Europe.

“The level of risk for NATO has simply and suddenly increased enormously,’’ said Ian Lesser, a former American official who heads the Brussels office of the German Marshall Fund. “The possibility of conflict with Russian forces in Europe or elsewhere, like the Black Sea, the Sahel, Libya or Syria, could be dangerous and will be an issue for years to come.’’

“This changes everything for NATO,’’ said Ian Bond, a former British diplomat who heads foreign policy at the Center for European Reform. “Russia’s aim is to extinguish Ukraine as a sovereign country in Europe. Now we need to worry about everything, and we need to get serious again.’’

NATO has already responded in a small way to the Russian buildup, sending some extra troops and aircraft into member states closest to Russia. On Thursday, NATO decided on further, unspecified deployments, and there are serious discussions about finally scrapping the 1997 NATO-Russia Founding Act, which put limits on NATO deployments in the eastern members and which Russia violated eight years ago, when it invaded Ukraine and annexed Crimea.

“Russia’s actions pose a serious threat to Euro-Atlantic security, and they will have geostrategic consequences,’’ said the NATO Secretary-General, Jens Stoltenberg. “We are deploying additional defensive land and air forces to the eastern part of the alliance, as well as additional maritime assets.’’

Any discussions with Moscow about redrawing Europe’s security architecture take on a different cast with Russian troops deployed on NATO’s eastern flank.

Even if military spending goes up considerably in response to the new Russian invasion, as it did modestly after Russia took Crimea, new and permanent deployments of forces, equipment, planes and even missiles will be a major blow to the last 30 years of relative peace, prosperity and complacency in the alliance.

“NATO had been focused on all these important and fashionable things with little to do with its core responsibility, like climate and cyber,” Mr. Lesser said. “But we forgot that there are ruthless people out there and for them, foreign policy is a blood sport.’’

NATO was already rewriting its 12-year-old strategic concept and debating a replacement for Mr. Stoltenberg, who leaves office on Oct. 1. Now, those tasks become ever more pressing. “NATO is already in a mode to think more broadly about its purpose,’’ Mr. Lesser said.

But a serious effort to deter a newly aggressive Russia will not be so simple, said Benjamin Hodges, the former commander of U.S. forces in Europe, now with the Center for European Policy Analysis. Just moving troops and equipment around in a post-Cold War Europe has become far more cumbersome, with some bridges and railways no longer able to handle heavy armor.

“Political leaders will be surprised at how long it takes to move stuff given E.U. road regulations and without special priority’’ on the German rail system, Mr. Hodges said.

NATO also lacks significant air and missile defenses for a modern air war that, as in Ukraine, starts by hitting significant infrastructure like airports, roads and rail, he said. Just to protect the large American air base at Ramstein, in southwestern Germany, would take an entire battalion of Patriot missiles, he said, “and we have only one Patriot battalion in Europe that’s ours.’’

Once the Fulda Gap in Germany was a worry of Cold War strategists, heavily defended by American troops to prevent the Warsaw Pact from rushing tanks from East Germany to the Rhine River. Now, the concern is the Suwalki Corridor, a narrow gap that connects Poland to Lithuania that, if captured, would cut off the three Baltic nations from the rest of NATO.

The corridor separates Belarus from Kaliningrad, headquarters of the Russian Baltic Fleet and isolated from Russia when the Soviet Union imploded. An emboldened Mr. Putin might very well demand direct access from Belarus to Kaliningrad, suggested Robert Kagan of the Brookings Institution in a column for the Washington Post.

“But even that would be just one piece of what is sure to be a new Russian strategy to delink the Baltics from NATO by demonstrating that the alliance can no longer hope to protect these countries,’’ he wrote.

“The threat now to Poland becomes acute,’’ said Mr. Bond, recommending that the United States quickly put two heavy battalions in Poland “for a start.” The deployments in the three Baltic states also need to be beefed up, he said.

In 2016, NATO agreed to put battalions in Poland and the Baltic nations for the first time. Known as an “enhanced forward presence,” they consist of about 1,100 soldiers each, combat ready but small, more like tripwires than anything that could slow down a Russian advance for very long.

In 2014, NATO also established a “very high readiness joint task force,’’ currently under the command of Turkey, that is supposed to deploy at short notice against threats to NATO sovereignty. It consists of a land brigade numbering around 5,000 troops, supported by air, sea and special forces, with more reinforcements able to be deployed within 30 days.

But the smaller force is essentially untested, and the larger Response Force of which it is the spearhead is only a quarter the size of the Russian invasion force into Ukraine. The larger force was created in 2002 and was meant to be rapidly deployable, but its 40,000 members are based in their home countries and gathering them can be a slow exercise.

There are also questions about the vow of NATO members to send weapons to Ukraine as it fights the Russians or to help mount an insurgency. Efforts to supply arms to Ukraine by air, rail or road could be intercepted or obstructed by the Russian military, Mr. Hodges said, even if the shipments are delivered by contractors and not NATO soldiers.

And what country is going to dare support an insurgency knowing that the Russian military is on the other side of the border?

In general the chance of accidental confrontations leading to escalation cannot be ruled out in such a tense atmosphere. Analysts point to the way Turkey shot down a Russian fighter plane near the Syria-Turkey border in 2015. “It didn’t escalate then, but today it very well could,’’ Mr. Lesser said.

At the same time, the arms control agreements that tried to keep the Cold War cold are nearly all defunct, raising new threats about deployments of conventional forces and medium-range missiles. Russia has also been extremely active in cyber warfare, hacking the German Parliament, interfering in the last French election and issuing mounds of local-language disinformation on social media.

Altogether, the new threats should reinforce the logic of stronger European Union and NATO cooperation on defense, Mr. Lesser said, “and should knock a lot of the politics and theology out of that relationship.’’ Coordinating with the E.U. over its areas of strength, like economic sanctions, cyber resilience, energy security and information warfare can only help both organizations, he said, given that 21 of the E.U.’s 27 members already belong to NATO and others, like Sweden and Finland, are closely allied.

“We need the Americans,’’ said Mr. Bond. “But we should not drop the idea of European autonomy and more self-reliance.’’ There are doubts in Europe about whether President Biden will run or win again in 2024 and worries that former president Donald J. Trump or a Republican more in tune with his isolationist, America first credo will take office.

“Europe will be very exposed, so it must increase military spending and efficiency, filling real capability needs,” Mr. Bond said. “All this becomes vital now, and not just a bunch of nice ideas.’’