Downvotes? What exactly sounds controversial about the advice? Anybody read 20th century history?

Besides, it's not like "terrorism" is some constant in societies. With the exception of nutjobs, organized terrorism is a response to specific political circumstances and relations between countries. You don't see any terrorism between the Swiss and the French. But there has been between the Irish and the British, for the well known historical reasons. Or in Spain with the Basque countries. Or in the Middle East / Latin American.

It's a political issue, and can be solved at that level, not some natural force that we no other mean to stop except to always be prepared for it, like earthquakes.