MIHAIL KOGALNICEANU AIR BASE, Romania — The soldiers of the U.S. Army’s 101st Airborne Division train, eat and sleep on a drab, sprawling post in southeast Romania, a mere seven-minute rocket flight from where Russia has stockpiled munitions in Crimea.
Farther north, in military exercises with Romanian troops just a few miles from the Ukrainian border, U.S. soldiers, also from the 101st division, are firing artillery, launching helicopter assaults and digging trenches similar to those on the front lines in the region near Kherson, the Ukrainian port city from which Russian troops retreated in November.
It is the first time the 101st Airborne Division has been deployed to Europe since World War II, and with their presence in Romania, a member of NATO, its soldiers are now closer to the war in Ukraine than any other U.S. Army unit.
Its mission is considered a model for an American miliary that has newly stepped back from two decades of actively fighting wars and into an era of trying to deter adversaries — using a show of force as well as training, weapons shipments and other aid to drive home the point.
“This is a regional conflict, but it has global implications,” the U.S. Army’s chief of staff, Gen. James C. McConville, said in a mid-December interview at the air base, which shares a runway with an adjoining commercial airport named for the former Romanian prime minister, Mihail Kogalniceanu, near the Black Sea.
The troop deployment in Romania is meant as a warning to Moscow, part of President Biden’s pledge to defend “every single inch” of NATO territory without tempting President Vladimir V. Putin of Russia into escalating. But holding joint exercises is also a way of ensuring that allies in southeast Europe are ready to hold the line.
But supporters of maintaining a strong presence in Eastern Europe pointed to Russia’s invasion of Ukraine in February as proof that the United States and its NATO allies did not do enough to deter Moscow last winter.
“This is one of the most important lessons that we have to take away from Ukraine,” Representative Seth Moulton, Democrat of Massachusetts, told reporters after returning from a brief trip to Ukraine in early December. “When we look at the other scenario that might unfold like Ukraine, in the Pacific with China and Taiwan, we have to ensure that deterrence is successful.”
Military planners echoed that strategy, noting that the 101st Airborne Division was also using the Black Sea for coastal defense training — a useful skill should China ever become more aggressive and invade Taiwan, a self-governing island that Beijing has long claimed as its own.
The division was ordered to deploy about 4,000 soldiers and senior commanders just weeks after Russia invaded. They arrived at the air base, near the Romanian coastal city of Constanta, over the summer. The base previously served as a sleepy outpost for training NATO troops, including several hundred American soldiers, and was known more broadly in the military as a way station with a small mess hall for U.S. forces heading to and from Afghanistan.
The mission here is somewhat different from those elsewhere in Europe, where some U.S. troops are training Ukrainian forces on advanced weapons systems that are being shipped to the Ukrainians. The division’s commander, Maj. Gen. J.P. McGee, said that training with other Eastern European soldiers had its own value.
“You get a chance to train and operate on the very ground that you might have to defend,” General McGee said.
He added: “You have to work with a NATO ally, and it’s almost unimaginable in the future that we would ever go fight without allies.”
In addition to the troops in Romania, General McGee has also sent smaller teams of soldiers to train with NATO allies in Bulgaria, Germany, Hungary and Slovakia. The unit prides itself on being the closest one to the combat, but it is by no means the largest: Officials said that an estimated 12,000 troops attached to the Army’s First Infantry Division, added after the invasion, are based mostly in western Poland and the Baltics.
Together, they represent a buildup of U.S. forces in Europe since Russia invaded Ukraine, as Mr. Biden promised allies at a NATO summit meeting in Madrid in June.
As part of military exercises with American and British forces, Romanian troops have been testing the HIMARS rocket launching systems — the same weapons that have helped Ukraine push Russian forces into retreat — against simulated targets in the Black Sea over the past few months. Romania bought three of the rocket systems years ago, and officials said they are still in the process of being delivered.
Lt. Gen. Iulian Berdila, chief of the Romanian land forces — who has welcomed the deployment — said regional officials had been warning the West of “incremental and toxic” advances by Russia since it seized control of Crimea from Ukraine in a 2014 local referendum that much of the world views as illegal.
“We’ve been very attentive to what Russia does, and what are the consequences,” General Berdila said. Of the training with U.S. troops, he said, “We’ve war-gamed together the different scenarios and are prepared to synchronize plans as we speak.”
The number and senior command level of American forces currently in Romania are enough, he said, for “predictable deterrence and defense together.”
General McConville would not predict what the Biden administration might do in Romania, but broadly speaking, he said the troops at the air base had “really made a difference, and I think we will continue to provide those capabilities as required.”
Having a division commander and staff so close to the border with Ukraine is more than symbolic, said Becca Wasser, a war analyst at the Center for a New American Security, a research institute in Washington. It allows for quick decisions about where to position thousands of troops and weapons should Russia push the war into NATO territory.
“What you are seeing is indicative of a change in how the U.S. military is approaching posture and deployments around the globe as the era of wars in Iraq and Afghanistan have changed,” Ms. Wasser said. “It’s not necessarily going to be this combat deployment — what you really have is a deterrence deployment.”
It is the same kind of mission, Ms. Wasser said, that was undertaken by tens of thousands of American troops sent to bases across the U.S. Central Command in 2020 as tensions with Iran flared across the Middle East.
For Command Sgt. Maj. Vitalia Sanders, who leads a battalion at Mihail Kogalniceanu air base, the mission is as personal as it is professional.
She was born in a town outside Uzhhorod, in western Ukraine, and moved to northwest Indiana when she was 12 to live with her grandmother. She was last in Ukraine in 2005, and her brother is still there — although their communications over WhatsApp and Facebook have been limited because Russian strikes have taken out power grids.
Sergeant Major Sanders has been in the U.S. Army for 21 years, and served in Afghanistan and Kuwait. But she never forgot the threat that Russia posed to Ukraine.
“Just being here, so close to home,” she said, “makes me hungry and makes me fight, and hopefully spreads that energy to soldiers to let them know how important this is for everybody.”
