ANKARA, Turkey—America’s allies are rushing to find workarounds and replacements for the bombers, warships and other forces the U.S. recently told other NATO members they could no longer rely on in a crisis.
But filling all the holes left by the American pullback—including midair refuelers that are in short supply and long-range strategic bombers that only the U.S. has—is proving challenging for the military alliance and risks leaving its European members, in particular, exposed to rising threats from Russia.
European leaders are set to take up the problem at the North Atlantic Treaty Organization’s planned annual summit in Ankara, Turkey, this week, where allied leaders will strive to maintain a veneer of unity despite divisions over the U.S. war with Iran and the Pentagon’s determination to shift assets to the Pacific.
“Europeans are already backfilling what the U.S. cannot any longer promise,” said NATO Secretary-General Mark Rutte in an interview with The Wall Street Journal.
Rutte acknowledged that “in some cases we’ve got more work to be done” on replacing American capabilities. However, NATO is better off having realistic expectations of what the U.S. can be certain of contributing, he added.
One workaround that seeks to make up for the lack of long-range strategic bombers: Deploy more long-range missiles on the ground and fighter aircraft in the sky.
NATO veterans and military experts say that Europeans can’t easily replicate or quickly replace some key military capabilities the U.S. has allocated for the defense of the alliance for decades, including long-range bombers, an aircraft carrier and submarines. The Trump administration cuts are immediate, they add, providing no time for a transition.
Retired Army Gen. Curtis Scaparrotti, who served as the alliance’s top commander during the latter months of the Obama administration and President Trump’s first term, said that any transfer of military responsibility from the U.S. to European nations must be carefully timed and required more preparatory work.
“I don’t agree with the uncertainty we have injected into the force posture,” he said. “If we determine there should be changes, it cannot be immediate and without preparation, in order to ensure deterrence against what is a real threat from Russia.”
Some former U.S. officials say that reduced dependence on America could make the alliance more reliant on nuclear forces to deter Russian aggression. A six-nation program dubbed “nuclear sharing” allows some European nations, including Germany, the U.K. and Turkey, to equip their aircraft with U.S. nuclear weapons in a war, an arrangement that Polish officials say they want to join.
“If NATO is less able to count on its conventional forces for deterrence, it makes the alliance more dependent on the credibility of American nuclear weapons,” said Celeste Wallander, who served as the assistant secretary of defense responsible for NATO and Russia policy during the Biden administration.
The U.S. cuts, which caught the Europeans and American lawmakers off guard recently, fall into two groupings: reductions to American Army brigades already deployed on the continent, and a scaling back of air, naval and other reinforcements the Pentagon had pledged to send in a crisis.
For the Trump administration, the twin moves signaled that it was time for Europeans to take the lead in the conventional defense of Europe—putting the U.S. in a better position to beef up its military in the Pacific to deter China, and deploy force in the Western Hemisphere. Washington has committed to maintain its nuclear umbrella over Europe, NATO’s ultimate defense against Russia.
But the abrupt moves unnerved many Europeans, particularly since Russia has stepped up its bombardment of Kyiv and is continuing to modernize its military. While Russia’s ground forces have been bogged down in Ukraine, its air, missile and naval assets remain largely intact.
The war in Ukraine—and Russia’s long-term goals of weakening NATO—are slated to be a top agenda item for alliance leaders’ summit this week, U.S. and European officials said.
Trump is expected to meet with Ukrainian President Volodymyr Zelensky on the sidelines, according to a senior Trump administration official.
Europeans accuse Russia of conducting a campaign of sabotage and nontraditional warfare across the continent that falls short of combat, yet signals Moscow’s malign intentions. Some European leaders say the hybrid attacks could herald a more conventional military attack in coming years.
“It is difficult and dangerous for the security of NATO’s European front when capabilities are withdrawn very quickly and before it is clear when these can be replaced,” German Defense Minister Boris Pistorius said last month.
European allies have largely filled the gaps left by the U.S. reductions, U.S. Air Force Gen. Alexus Grynkewich told the Journal. “In those few areas where they haven’t, where they do not currently have a like capability to replace, we are looking at alternate capabilities with matching effect,” he said.
In an effort to fill the gap, Allied officials said, European nations have now committed all of their new fighter aircraft to NATO’s defense instead of holding some back for their national missions.
Discussions about deploying more ground-based long-range missiles and fighter aircraft in place of long-range strategic bombers are currently taking place, Western officials say. However, replacing U.S. capabilities in midair refueling won’t be easy and would require establishing more airfields with fuel capacity, the officials add.
But there are skeptics.
“Ground-based long-range fires can supplement, but they cannot come anywhere close to the reach of a bomber or replicate the bombers’ capability to quickly revisit targets,” said David Deptula, the dean of the Mitchell Institute for Aerospace Studies and a retired Air Force three-star general. “Fighters cannot carry as great a payload as bombers and have less reach, and when you look at a nation the size of Russia, range matters.”
While Europe has drastically scaled up military spending in recent years, its defense industry, freshly infused with new cash after decades of laggard investment, is now grappling with major production bottlenecks to delivering sorely needed arms and munitions in a timely manner.
“The big issue I think that Europeans should be focusing on is the industrial cadence and capacity to actually deliver in a much quicker way to meet the moment,” said Alexandra de Hoop Scheffer, president of the German Marshall Fund, a think tank.
The scaling back in reinforcements comes as the Trump administration reduced the number of American troops it has arrayed on the continent, a footprint that has long provided a tangible demonstration of U.S. commitment to NATO.
In May, the Pentagon canceled the deployment of an armored brigade to Poland from Fort Hood, Texas. Trump said later that he would send 5,000 troops to Poland, though the Pentagon hasn’t so far sent more forces to the country. That followed the Trump administration’s move last year to remove an infantry brigade from Romania.
The Pentagon has also halted the deployment of an Army battalion equipped with long-range missiles in Germany.
In Washington, leading Republican and Democratic lawmakers have sought to stop the Pentagon from removing additional troops by inserting provisions in pending military-spending legislation that would bar U.S. troop levels from falling below 76,000 without further review.
Another battle is brewing over U.S. stocks of Army weapons and equipment kept in Europe.
U.S. European Command aims to field four armored brigades during a crisis. To hedge against troop cutbacks, the command wants to ensure adequate supplies of weapons and equipment are kept in Europe. That would speed the deployment of American troops in the event they are rapidly flow in from the U.S. But the Pentagon so far hasn’t locked in the necessary funding.
Congress is also moving to block the removal of any of the Army stocks in Europe, which Pentagon officials say would infringe on Trump’s prerogatives as commander in chief.
“I think the department is fundamentally miscalculating the advantage from prepositioning stocks and equipment in Europe,” said Sen. Jeanne Shaheen, a New Hampshire Democrat who serves on the Senate Armed Services Committee.
Write to Michael R. Gordon at michael.gordon@wsj.com, Daniel Michaels at Dan.Michaels@wsj.com and Robbie Gramer at robbie.gramer@wsj.com
