They are the most advanced fighter jets in the world, capable of flying at 1,200mph while staying virtually invisible to enemy radar, equipped with unrivalled surveillance capabilities and a devastating array of missiles.

Every year roughly 150 new state-of-the-art planes, which have quickly become the backbone of modern Western air forces, rise from a base in Fort Worth, Texas, for delivery around the world.

But serious doubts about the programme that brings billions of dollars into the US have emerged in recent weeks due to one burning question – can allies rely on America any more?

Trust in the US security umbrella has rapidly drained as the Trump administration appears to move away from Europe and by some measures closer to Russia, all the while threatening to annex Greenland or Canada, and falling out spectacularly with Ukraine’s Volodymyr Zelensky.

Such is the anger at the US over its foreign policy pivot, some are even asking whether F-35s could become the new Tesla – the world-beating vehicle that was once the envy of rivals but is now facing a damaging boycott.

Major allies have already raised doubts over future orders, while France announced last week a massive expansion in its own domestic fighter jet production as Europe looks to “onshore” its defence industries.