Security has been stepped up in the UK, but everywhere else it's business as usual

Since the alleged terror plot against the airlines was foiled nearly a week ago, security has been stepped up at UK airports and heavy restrictions are likely to remain for the forseeable future. The question is, what difference will it make? In the rest of Europe, nothing has changed. What's to stop a Jihadist (there are plenty of them in the rest of Europe) from boarding a flight leaving Paris or Amsterdam to the US or the UK? The rest of Europe's airports are being remarkably complacent.