The debate over a potential withdrawal from the US F-35 fighter jet program is heating up in Germany and other European countries.

The background to this is that the jet can only be used with the approval of the US government, and restrictive provisions, for example regarding spare parts and software, make it impossible to escape dependence on the US in military operations with the F-35.

In Berlin, former “transatlanticists” in particular are pushing for withdrawal from the F-35 procurement program to achieve military independence.

Last week, a copy of the purchase agreement for the 35 F-35 fighter jets that Berlin decided to procure in March 2022 was leaked to the German magazine Stern. Details of the framework conditions for the purchase, which will cost €8.3 billion, thus emerged.

This purchase is being handled as part of the Foreign Military Sales (FMS) process, which is subject to strict rules. The F-35 purchase agreement grants Washington the authority to “terminate or suspend performance in whole or in part” without further notice “if required by the national interests of the US.” This means the US can unilaterally change the delivery time and quantity at any time. Contractual penalties are generally not provided for in the FMS procedure; legal recourse is excluded.

Once an F-35 fighter jet is delivered, no further modifications are permitted; spare parts and regularly required software updates are only available from the US manufacturer Lockheed Martin. According to the wording in the purchase agreement, “The customer is not authorized to carry out repair and maintenance work beyond the unit maintenance level.” This already guarantees that the German Air Force’s F-35s will only fly when the US administration wants them to.

Furthermore, the F-35’s basic software is kept secret. Therefore, it is impossible to check whether the jet can be influenced externally, but many assume this is possible. Data generated during operation, and especially during any mission, is collected and subsequently stored on Amazon Web Services, making it easily accessible to US authorities.

Finally, the US Foreign Assistance Act allows the US to “monitor the end-use” of the F-35 “at any time.” A “well-informed” source told the magazine Stern, claiming, “Targets, routes, indirectly tactics… US technicians are always on the plane.” An insider with “intelligence service knowledge” also explicitly confirmed this to the magazine, stating that “all mission planning is monitored in the US.”

Since last week, calls have been growing louder in Europe to avoid procuring F-35 jets if possible, or to withdraw from the agreement if a contract has already been signed. This was triggered on the one hand by the Trump administration’s decision to prohibit Ukraine from using US satellite data, and on the other hand by Washington’s continued efforts to acquire the autonomous Danish territory of Greenland.

For example, Danish conservative MP Rasmus Jarlov stated on X that he now regrets supporting Denmark’s decision to purchase 27 F-35 jets for its air force. Jarlov said, “I can imagine a situation where the US demands Greenland from Denmark and threatens to disable our weapons.” Jarlov argued that Copenhagen would then no longer be in a position to defend itself, making the purchase of US weapons “a security risk we cannot take.” He contended that Denmark will invest heavily in armaments in the coming years and should avoid American weapons wherever possible.

Some NATO countries are now considering abandoning the F-35. For example, Canada plans to withdraw from the F-35 purchase, but has already paid for 16 fighter jets due to be delivered early next year. According to Defense Minister Nuno Melo, Portugal, which previously planned to buy the US fighter jet, is also changing its mind. The French company Dassault Aviation has now offered to supply Rafale jets to the Portuguese government.

The Rafale is a fourth-generation fighter jet, unlike the fifth-generation F-35, but it is cheaper and requires no US components, thus offering independence from the US. French President Emmanuel Macron argued on March 16 that European countries should, in principle, switch from the F-35 to the Rafale; furthermore, the new Franco-Italian SAMP/T air defense system could be used instead of the US Patriot air defense system.

One challenge stems from the fact that a number of European NATO countries, such as the United Kingdom, Norway, the Netherlands, Belgium, and Italy, already possess F-35 jets. Many other countries, including officially neutral Switzerland, have placed binding orders for the aircraft.

Conflicting voices are also rising in Germany. Former “transatlanticists” in particular are distancing themselves from the F-35 procurement. Former Airbus CEO Thomas Enders, now president of the influential think tank German Council on Foreign Relations (DGAP), said last week, “Nobody needs the F-35”; Enders added that he “would be the first to cancel it under these new geopolitical conditions.” CDU foreign policy expert Roderich Kiesewetter also called for a “review of existing contracts with the US,” such as the F-35 purchase agreement, stating, “It is now absolutely essential to look for alternatives.”

Defense Minister Boris Pistorius, however, favors continuing with the F-35 purchase. One of the reasons he cites for this is nuclear sharing, whereby German Air Force fighter jets could drop US nuclear bombs in a war scenario. Observers note that dropping US nuclear bombs is already only possible on orders from Washington, making it irrelevant whether the F-35s could be paralyzed by the US as long as they are available solely for nuclear sharing. However, nuclear sharing itself is no longer considered secure.

Berlin has already transferred approximately $2.42 billion to Washington for the F-35 and has begun costly modifications at Büchel Air Base, where the US fighter jets are to be stationed.