Not only has the US unilaterally introduced these requirements already 15 years ago, but there are still 3 EU countries (Bulgaria, Cyprus and Romania) that are

Not only has the US unilaterally introduced these requirements already 15 years ago, but there are still 3 EU countries (Bulgaria, Cyprus and Romania) that are not even in the Visa Waiver Program - so I think some "retaliation" is in order...