The recent decision by President Donald Trump to withdraw 9,500 American troops from Germany by September 2020 carries with it a deep risk of doing irreparable damage to NATO, the most successful and effective defense alliance in history. Any weakening of NATO will ultimately weaken America itself. NATO has been under increasing stress in recent years, and this unilateral action by the alliance’s senior partner may become the final pressure point that will lead to the fracturing of the alliance. If that happens, it will collapse the security framework established and led by the United States since 1945.

During the years between the two World Wars, Army Maj. Gen. Fox Conner was one of America’s most important strategic thinkers. He was also a senior mentor who nurtured the professional development of many up-and-coming younger officers who would go on to be among our most important military leaders of World War II. Conner’s proteges included George Marshall, Dwight Eisenhower and George Patton. The three key principles of national military strategy he impressed upon those officers included: 1. Never fight unless you have to; 2. Never fight for long: and 3. Never fight alone. It is this third principle that we presently are most at risk of falling away from.

Maintaining an alliance is hard work. Each member of the alliance must find its own unique path to striking a balance between its external obligations to the alliance and its internal domestic and political dynamics. There is no question that some NATO members in recent years have been slow to meet their obligation to devote 2% of their GDP to their defense budgets. Those allies should be pressed to meet their obligation. But should this become the point upon which the very viability of the alliance hangs?

Germany, of course, has been one of the most reluctant of our partners to meet the 2% obligation. But that does not mean that Germany has been getting a “free ride” on security from the United States. Germany’s economic and political power currently make it the most important member of NATO after America, especially following the withdrawal of the United Kingdom from the European Union. German support for America both within NATO and globally is one of our most important bilateral partnerships. Russia and China understand that only too well, which is why they devote so much effort to fracturing that partnership by pressuring Germany to accommodate their own various regional and global initiatives, often to America’s disadvantage.

To measure Germany’s true commitment to the trans-Atlantic alliance, one only needs to look to the NATO mission in Afghanistan, as compared to Russia’s experience there in the 1980s. The Soviet Union went into Afghanistan alone, without the support of its Warsaw Pact allies. Ten years later, it came back out alone, having accomplished nothing. America, on the other hand, has had the full support of NATO in Afghanistan. Between 2002 and 2013, 57 Germans died in Afghanistan — the first German combat deaths since the end of World War II. The expenditure of national funds in support of the alliance is one measure of commitment, but it pales in significance with a nation’s willingness to risk the lives of its citizens in support of a cause or a mission.

American troops first entered Germany in 1945 as the occupying power of a defeated nation. Over the next 45 years Germany became the central base — but not the only base — from which to defend Western Europe against Soviet aggression. The reason Germany was the central position was because any ground war most likely would have been fought there. Generations of German citizens grew up under that shadow, which along with the memory of the two World Wars accounts for the deep ambivalence many Germans still feel about military matters.

Since the end of the Cold War, the strategic situation has changed. American forward military presence on German soil is now even more important to the United States than it is to Germany. As the home of both U.S. European Command and U.S. Africa Command, Germany currently hosts the command and control headquarters for American operability into three continents. They are an ocean closer to many of the world’s most dangerous trouble spots. It would be impossible to work at the same level of effectiveness if those headquarters had to operate from the continental United States.

Consider what Germany currently plays host to. Ramstein Air Base is the largest and most important American air base outside of the United States. Landstuhl Regional Medical Center has saved the lives of countless American and allied soldiers seriously wounded or injured in Afghanistan, Iraq, and other locations in Africa and Southern Asia. The 21st Theater Sustainment Command in Kaiserslautern coordinates and manages almost all American military logistics and transportation operations from Europe eastward. The Grafenwohr training center in Bavaria is America’s largest live-fire maneuver training ground outside of the United States. Military forces of allied and other partner nations also exercise at Grafenwohr, often in coordination with U.S. units. Thus, Grafenwohr is one of the world’s most important bases for interoperability training.

All of these nodes, of course, continue to play key roles in the security of Europe. But their spans of responsibility and operations extend today far beyond the boundaries of Europe. They are the foundations of America’s global operability. Weakening those foundations can only be to the advantage of our global adversaries — most dangerously, Russia and Iran.

All of these vital nodes of American global operability physically based in Germany are completely dependent on German infrastructure to function. Without being able to tie in directly to the German communications, transportation, internal security and public services networks, those American nodes would be absolutely incapable of performing their missions.

I saw this firsthand at the start of Operation Iraqi Freedom in early 2003. I was detailed as the director of the U.S. Army Europe Deployment Operations Center. It was an ad hoc control cell responsible for planning and coordinating the movement of some 30,000 V Corps troops and all their equipment out of Germany and into the Gulf region. Although Germany declined to participate in Iraqi Freedom, and even directly opposed it in the United Nations, the German government nonetheless bent over backward to help us get everything quickly and efficiently through the German rail, road, barge and port networks.

Quite frankly, the Germans could very easily have locked up V Corps in Germany. Virtually all of the troops headed for the Gulf flew out of Ramstein. The 173rd Airborne Brigade’s March 26 combat jump into northern Iraq depended on all the C-17s staging initially out of Ramstein, before picking up the troops in Italy. And as soon as the 173rd secured the airhead, a company of M1-A1 Abrams tanks flew from Ramstein on C-17s directly into the Bashur Airfield in Iraq. It was history’s first air-landing of main battle tanks directly into a combat zone. At no time did the German government, despite its stated opposition to Operation Iraqi Freedom, impose freedom of movement restrictions in or out of Ramstein. Turkey, in contrast, routinely causes difficulties about freedom of movement in and out of Incirlik Air Base.

The Germans also went all-out on the security end, working with us to secure the troop and equipment movements and screen them as much as possible from the various left-wing protest groups. As the remaining American troops became very thin on the ground in Germany, the Bundeswehr took over the responsibility for the perimeter security at many of the Army bases in Germany. Very few people outside of Germany ever heard anything about that.

By hosting so many centers of American military power on its soil, Germany becomes a lightning rod for the likes of Vladimir Putin and Xi Jinping. The Germans also pay a continuing price in terms of internal political tensions. Compounding those stresses, too many German citizens in recent years have come to feel that the United States now regards their country as a satellite state, rather than as a respected partner. That the decision to withdraw 9,500 troops was announced apparently without consulting with or even first notifying the German government has exacerbated that perception throughout the country.

Many commentators in Germany have denounced that decision as mere petty retaliation, because Chancellor Angela Merkel declined the invitation to attend the proposed G-7 summit in Washington. Whether or not that was actually a factor, the timing and the optics are not good.

There is a great deal more to support for NATO than just meeting the 2% obligation. It is important; but it is not the total picture. Compare Germany’s 1.39% contribution to Turkey’s 1.89%. But which country is the more dependable and vital ally?

There is a tragic trend developing here. Similar thinking is one of the key reasons that the Warsaw Pact was a failure. We cannot afford to let NATO slide down that same slope. We need to think very carefully about the second- and third-order effects of this decision to withdraw 9,500 troops from Germany. We also must work to develop more creative and constructive approaches to strengthening NATO and our ties to our security partners. If “America First” deteriorates into “America Alone,” the only winners will be China, Russia, Iran and North Korea.

David T. Zabecki, a retired U.S. Army major general, is a Fellow of the American College of National Security Leaders. He was director of the USAREUR Deployment Operations Center from January to June 2003. During the second half of 2003 he was the senior security adviser on the U.S. State Department’s U.S. Coordinating and Monitoring Mission in Israel, charged with overseeing the Roadmap to Peace in the Middle East initiative. From January 2005 to March 2006 he was commanding general of the Southern European Task Force Rear (Provisional), and simultaneously the American co-chairman of the Italian-American Joint Military Commission.

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