In a move which will give the US cloud suppliers apoplexy, the Justice Department has petitioned the US Supreme Court to allow US search warrants to extend to data stored on foreign servers.

The US government says it has the legal right, with a valid court warrant, to reach into the world's servers with the assistance of the tech sector, no matter where the data is stored.

The request for Supreme Court intervention concerns a four year old legal battle between Microsoft and the US government over data stored on Dublin, Ireland servers. The US government has a valid warrant for the e-mail as part of a drug investigation. Microsoft told it to go forth and multiply. It convinced a federal appeals court that US law does not apply to foreign data.

The government told the justices that US law allows it to get overseas data, and national security was at risk.

"This Court should grant review to restore the government’s ability to require providers to disclose electronic communications—which are, in this day and age, often the only or the most critical evidence of terrorism and crime," the government wrote.

If the Supremes agree then the EU will almost certainly respond by banning all US technology companies from operating in the bloc. The issue is that if US technology companies have to hand over data to US spooks then effectively no European data is safe.

Congress is trying to hash out legislation that would allow the US government to enter into reciprocity agreements with other countries so that each side has the right to access data on foreign servers—with a valid warrant.

But it is unlikely to go down well with any European country other than the UK which is desperate for friends. In fact Teresa May would sell the Americans Scotland if she thought it would get a decent trade deal.