Pedestrians pass by an embossed Bank sign at the entrance of a branch of the Swiss banking giant UBS in Zurich. - 

Today is the deadline for Switzerland's private banks to decide whether to cooperate with U.S. demands to combat tax evasion by handing over client information -- a move that would finally end the long tradition of banking secrecy.

For 5 years, the U.S. has been pressuring Swiss banks to hand over information on American clients who may have untaxed cash in Switzerland. Washington, struggling with a massive budget deficit, is chasing every last cent of tax revenue. But the deal offered -- hand over the information and face fines, or don't hand it over, and face prosecution -- has caused fear and anger, says Swiss member of parliament Christian Lüscher.

"Everyone is very afraid. Let's be completely honest, people are terrified, and that fear is legitimate, because no one is really sure how they will be treated," Lüscher says. "They could be eaten alive by the U.S. authorities."

The Swiss government says the banks should comply, the logic being fines are better than going out of business altogether. Many banks have already got rid of their American clients and probably will cooperate, marking another stage in the long death of Swiss banking secrecy.