More snooping

The US government is up to more snooping, this time on Europeans travelling to the U.S. Frankly, I don't understand why the European Union is putting up with this, but I would think the travelling public would be pretty p.o.'d. We must be holding a pretty big cudgel over their heads:

Britons flying to America could have their credit card and email accounts inspected by the United States authorities following a deal struck by Brussels and Washington.

By using a credit card to book a flight, passengers face having other transactions on the card inspected by the American authorities. Providing an email address to an airline could also lead to scrutiny of other messages sent or received on that account.

The extent of the demands were disclosed in "undertakings" given by the US Department of Homeland Security to the European Union and published by the Department for Transport after a Freedom of Information request.

About four million Britons travel to America each year and the released document shows that the US has demanded access to far more data than previously realised.

Not only will such material be available when combating terrorism but the Americans have asserted the right to the same information when dealing with other serious crimes.

Shami Chakrabarti, the director of the human rights group Liberty, expressed horror at the extent of the information made available. "It is a complete handover of the rights of people travelling to the United States," she said.

Question: Do the same rules apply to data from American citizens returning home? If not, why not? If so, is this a violation of the F.I.S.A. law?