Will Trump break the transatlantic alliance?

EUROPE

Military retrenchment and recurring trade disputes will strain relations between the US and Europe, creating uncertainty that Russia is likely to exploit. But their deep strategic ties make complete decoupling unlikely.

THE US and Europe are likely to endure three years of military retrenchment, trade disputes and political volatility without severing the alliance that has underpinned Western security for decades, a new report finds.

But uncertainty over America’s commitment will create an opportunity for Russia to test NATO’s cohesion through drone incursions, cyberattacks and sabotage, even if Washington ultimately stops short of abandoning Europe.

The Sibylline report assesses a 50% probability that the US will gradually scale back its military presence while recurring economic disputes drive uncertainty and investment pressures.

Despite Donald Trump’s repeated threats against European allies, deep military, economic and technological interdependencies make a definitive transatlantic split unlikely before he leaves office.

The US is unlikely to withdraw formally from NATO, while co-operation will continue across intelligence, surveillance, command-and-control systems, satellite communications and airborne early-warning capabilities.

Report co-author and Sibylline Lead Europe Analyst Alex Lord says even a deliberate attempt by both sides to disentangle their relationships could not be accomplished quickly.

“The realities of economic, military, technological and financial entanglement mean that, even if both sides wanted to decouple, it would take time and would be relatively painful,” he says.

The report examines the remaining three years of Trump’s presidency and distinguishes between the administration’s confrontational rhetoric and decisions that would materially weaken Europe’s security.

Washington is expected to retain a provision in the National Defense Authorization Act preventing the number of US personnel stationed in Europe from falling below 76,000.

Trump preserved the Biden-era safeguard when he approved the legislation for the 2026 financial year, despite frequently reversing his predecessor’s policies and demanding that European allies assume greater responsibility for their own defence.

Sibylline Lead Americas Analyst Lewis Galvin says congressional support for NATO remains significant.

“There are still a lot of people in Congress, and a lot of Republicans, who support bolstering European defence,” he says.

“It is not as though the entire Republican Party is on board with stepping back from Europe.”

Galvin argues that Trump is using the possibility of military withdrawal chiefly as leverage to secure strategic and economic concessions.

“I think it’s a lever,” he says.

“He wants more preferential access for the US, and he wants that relationship to benefit the US as much as economically possible.”

This includes securing greater access for US companies, increasing European purchases of American energy and defence equipment and persuading European governments to reduce their reliance on China in sensitive sectors.

Trump could also use US deployments to distinguish between governments he regards as dependable partners and those he accuses of failing to contribute sufficiently to the alliance.

“President Trump has made it clear that he wishes to reward so-called good allies and, to an extent, punish so-called bad allies,” Lord says.

“There is a scenario where US troops and wider military commitments are used as a visible show of favour and disfavour.”

The planned withdrawal of 5,000 US personnel from Germany does not necessarily amount to a broader retreat from the continent.

Troop numbers fluctuate because of rotations and scheduled redeployments, while personnel removed from Germany could be stationed elsewhere in Europe.

The more significant test would be whether Washington begins removing capabilities that European NATO members cannot rapidly replace.

“If the US Army Brigade Combat Team in Germany were withdrawn, that would represent a significant loss of capability,” Lord says.

“That would probably be more concerning to European NATO members than simply drawing down 5,000 troops.”

The withdrawal of American air and missile defence systems, long-range strike assets, intelligence support or command infrastructure would create serious operational gaps.

A phased reduction over 12 to 18 months would give European allies limited time to reposition forces across the Baltic states, Poland and Romania.

However, the report finds that Europe would remain unable to replace every lost US capability in the short to medium term.

Russia would probably exploit that period by intensifying hybrid operations along NATO’s eastern flank, including co-ordinated drone incursions, cyberattacks against military logistics and sabotage targeting railways, energy infrastructure and critical subsea cables.

Moscow is likely to stop short of a major conventional assault because it would not want to reunite NATO or reverse an American withdrawal.

Nevertheless, miscalculation would keep the risk of armed conflict high, even if a ceasefire is agreed in Ukraine.

The report assesses a 38% probability that strategic competition with China produces the opposite result and strengthens transatlantic ties.

Washington needs European support to protect critical supply chains and reduce Chinese involvement in critical minerals, artificial intelligence, cloud infrastructure and energy.

Europe also provides the US with strategic access to the Arctic, a market for American arms and energy, and bases that support US power projection into the Middle East.

However, Galvin warns that Trump must avoid placing so much pressure on European governments that they turn towards Beijing.

“It’s a major balancing act that Trump has to get right,” he says.

Economic interdependence also constrains both sides.

Germany and Ireland are among the European economies most exposed to US tariffs, while a prolonged trade war would inflict significant costs on American businesses and consumers.

The report assigns only a 12% probability to its most dangerous scenario, in which deteriorating relations make Washington’s participation in NATO increasingly selective and seriously undermine the credibility of Article 5.

The likelier future is an alliance that becomes more transactional and unpredictable without disintegrating. Europe will pursue greater strategic autonomy, but continue buying American weapons and depending on US military capabilities.

Lord says the ties binding the US and Europe will be far harder to break than the political rhetoric suggests.

“Irrespective of the rhetoric and the threats, the depth of the institutional, economic and technological interdependencies is such that rapid decoupling would not only be politically and economically unwanted, but would likely be impossible.”