They'll immediately ban EU flights into the USA costing EU airlines a shitload of money and EU companies too.
Then they'll have to give in and allow the data so flights can resume and demand equally silly quid pro quo stuff.
Don't buy from US companies (Kraft, Apple, MuckDonalds, MS, etc). Then EU companies have less reason to deal with the USA, meaning flights to the USA become less important and tourists will always find somewhere else to fly to... Yeah some stuff is really US-only like CPU's but you can always buy a SONY or Samsung laptop to keep it in, HTC / LG instead of Apple or Motorola, etc...
The yanks.gov will do whatever they want regardless but consumers don't have to help fund their economy.