"The ultimate military purpose of war is the destruction of the enemy's ability to fight and will to fight."

ISIS is at war with us, therefore we need to understand warfare to understand what's going on.

The whole point of warfare is to destroy the enemy's will to fight. Otherwise military strategy wouldn't exist. Encirclement, propaganda, shock and awe, Blitzkrieg, element of surprise, all of those are primarily elements of psychological warfare. If persuade your enemy that you've already won, it becomes a self-fulfilling prophecy.

ISIS's goal isn't to get Europeans to turn against Muslims. Their goal is to destroy Europeans' will to fight. The people saying "terrorists want a reaction out of us! we shouldn't react!" are siding with ISIS. No-reaction is how you treat bullies, not murderous enemies that are trying to destroy you.

Every country with a large Muslim population has terrorism. We're bringing this to Europe. a) Muslims have higher birthrates, and b) more are coming through immigration, so this will get worse over time.

The fact that the poster says "#Londonisopen" proves my point, and tells you everything you need to know.