A ‘Kill Switch’ Could Shutter Europe’s Access to US Tech. Here’s How.

Trevor H. Rudolph is the former Chief of the Cyber and National Security Unit at the White House Office of Management and Budget. The opinions expressed here are his own and do not reflect the positions of his employer.

The transatlantic relationship has had many points of tension in recent years. During the Biden administration, disputes arose concerning the US Inflation Reduction Act’s purported preferential treatment of US firms and US-based manufacturing. Ties were also strained by the Biden administration’s restrictions on the sale of advanced artificial intelligence (AI) chips to European allied nations through its AI Diffusion Rule, which the Trump administration later rescinded.

However, the Trump Administration has escalated the tensions to new levels. Since taking office, the Trump administration has accused the EU of unfair trade practices and ill treatment of US technology firms, mused about abandoning NATO allies with insufficient defense contributions, sanctioned the International Criminal Court (ICC), curtailed US aid to Ukraine, temporarily paused intelligence sharing with Kyiv, and repeatedly expressed a desire to annex Greenland. Now, the Trump administration is reportedly weighing the unprecedented step of sanctioning European officials responsible for the implementation of the EU’s Digital Services Act.

Unsurprisingly, many Europeans are on the lookout for alternatives to US technology and services. Following the temporary pause of US intelligence sharing with Ukraine, Europeans began to consider the risk that Washington could unilaterally cut off European access to a wide range of US-provided services, including military intelligence, weapons systems, and even consumer-focused cloud services. Framed as a proverbial “kill switch” by many in Brussels, the debate has shifted from whether it could be triggered to when. This, in turn, has prompted renewed calls by the EU and member states to advance the continent’s “technology sovereignty.”

What is termed the “sovereign cloud” has become the practical implementation of technology sovereignty objectives. The idea is that Europe should have its own alternatives to US cloud providers, which many fear could be subject to the political whims of the current US administration. The term dates back to at least 2016, initially when it was used to describe French efforts to secure cloud infrastructure that would be shielded from US law enforcement data requests under laws like the US Cloud Act and the Patriot Act. Renewed fears of a possible kill switch have only accelerated European efforts to become independent from US technology.

In response, US cloud providers now market their own version of “sovereign cloud” to address European concerns, ranging from Microsoft’s recently announced “European digital commitments” to AWS’s promise of “control without compromise,” with varying degrees of localized infrastructure and data control. Yet many Europeans are skeptical. French Digital Minister Clara Chappaz denounced European dependence on US cloud providers at an April event, pointing out that Google Cloud, Microsoft Azure, and Amazon Web Services (AWS) collectively control up to 80 percent of the European market and further warned against what she calls “sovereignty washing.”

This sentiment has helped catalyze efforts such as the strategic partnership in Luxembourg between DEEP and OVHcloud, announced in March. As DEEP’s director, Sébastien Genesca, said of the deal, "This strategic partnership allows us to offer a fully sovereign and local cloud infrastructure, protected from extraterritorial laws.” Although it’s still unclear if such an effort can scale to one day challenge the dominance of US cloud providers, threats of a kill switch may hasten the rise of similar alternatives.

How a kill switch might be activated

Are European fears of a kill switch warranted? It depends. While the concern is understandable, the likelihood that a US president would unilaterally terminate European access to US technology is still remote. The US-EU trade and investment partnership is the largest in the world, totaling 1.6 trillion euros in 2023. Even hinting at such an option could irreparably damage the transatlantic relationship and could erode the dominant position of American technology in Europe, an outcome any US administration should want to avoid.

Regardless of how remote this scenario may be, is it even possible for the Trump Administration or any future administration to terminate European access to US cloud-based services? The direct answer is, yes—at least in the short term. In such a scenario, the US would likely draw on a mixture of statutory authorities and policy tools at the president’s disposal.

One option, as seen in the public dispute between US President Donald Trump and Elon Musk, would be to threaten federal contracts held by US technology providers if they continue to service European customers deemed to be working counter to US interests. Even though such a move would likely trigger legal challenges from the companies involved, the mere threat would push Europeans to accelerate their efforts to develop alternatives, even as some EU cloud-industry estimates already predict a double-digit increase in EU-based sovereign cloud market growth between 2022 and 2027.

Another option would be invoking the International Emergency Economic Powers Act (IEEPA), which grants sweeping authority to regulate commerce when an emergency is declared. By statute, such an emergency must pertain to “any unusual and extraordinary threat, which has its source in whole or substantial part outside the United States, to the national security, foreign policy, or economy of the United States.” President Trump has already said that he views European regulations and non-tariff barriers as running counter to US economic interests and has likened these activities to “taxation.” Once an emergency is declared, the president has broad authority to regulate or terminate relevant commercial transactions that relate to the emergency. While applying IEEPA in this way would be unprecedented, the President could, in theory, target foreign transactions of cloud providers servicing European private and/or public customers.

In light of the US Court of International Trade’s May ruling rejecting the Trump administration’s use of IEEPA to justify its tariffs, it is reasonable to ask how durable the invocation of IEEPA would be in the scenario envisioned here. However, history has shown that the courts are generally deferential to the executive when it comes to the invocation of IEEPA.

The Congressional Research Service has found that although there have been numerous lawsuits seeking to overturn uses of IEEPA, “most of these challenges have failed, and the few challenges that succeeded did not seriously undermine the overarching statutory scheme.” This suggests that the bar for overturning any use of IEEPA, regardless of how novel, is likely high. If meaningful limits are to be placed on the use of IEEPA, it will fall on Congress to exercise its oversight of an administration’s use of the law and clarify key definitions, such as what constitutes a national emergency, especially in economic contexts.

Finally, an administration could leverage export controls. The president has the authority to add European customers or even entire countries to the Commerce Department’s Entity List if they are deemed to be acting against US interests. In that case, US technology firms would then require a license to export US technology to these designated European entities, potentially grinding services to a halt. To close any loopholes involving US technology manufactured and deployed abroad, the president could also apply foreign direct product rules against certain classes of technology, further restricting flows to countries labeled as adversarial. Such measures could be devastating for both US providers and European customers who rely on their services.

A US president could use any of these tools in isolation or as part of a more coordinated, step-by-step strategy to maximize damage to perceived adversaries. The president could also choose to target the entire EU or take a more selective approach, restricting access to certain member states while leaving others, perceived as more friendly to US interests, with unfettered access. Pursuing this “winners” versus “losers” approach would likely create chaos within the EU and deepen reliance on US technology in the short term, but, over time, it would ultimately force the entire bloc to look for reliable alternatives.

Avoiding a digital divorce

As it did in the days following Trump’s “Liberation Day” tariffs, the EU would likely debate turning to its Anti-Coercion Instrument (ACI), which was conceived in 2023. As my Atlantic Council colleagues have noted, the ACI allows the European Commission to retaliate against economic coercion through a range of measures, including, but not limited to, “applying export controls, restricting intellectual property rights, curtailing foreign investments, banning services, or applying duties to digital platforms. The tool could also be used to exclude access to the European single market and public-procurement tenders.” Importantly, these retaliatory measures do not require unanimity to go into force, but only approval from 55 percent of the bloc’s twenty-seven members. As this instrument has never been used before, it is unclear how effective this form of retaliation would be, or whether the costs and unintended consequences would outweigh the benefits.

The bigger risk for Washington is long-term strategic drift. As China and Russia have demonstrated, when countries are cut off from accessing key technologies, they double down on developing local alternatives, skirt the restrictions altogether, or both. That may be an outcome the US can live with for countries deemed to be adversarial, but it’s not a risk that the US can afford to take with a reliable and relatively friendly market like the EU.

As I’ve written before, the transatlantic relationship is mutually beneficial and reinforcing, especially as it relates to technology. The United States and the EU are already in the middle of intense discussions to finalize the recently announced trade framework, which likely helped avert a larger trade war. Avoiding a digital divorce should be a component of these talks. To preserve US technology leadership in Europe, the Trump administration could ease tensions by providing explicit assurances that a kill switch is not on the table. In return, European officials could make equally clear that US technology firms willing to play by EU rules will continue to have access to European markets. The contents of the trade framework should not just be about reducing tariffs and non-tariff barriers, but about getting the relationship back on track so that both economies can flourish.