The UK and the US really head the current hegemony that is currently instilling so much war in the world. I believe the EU does share this responsibility, but I also really hope the UK leaving the EU helps the rest of Europe in in pushing back against these covertly back wars in Syria and elsewhere.

British citizens may not be able to world and live throughout the EU any more either. People already abroad may lose their work status on nations without reciprocal fall-back agreements.

This is a pretty big change, but I don't think it's a bad one.