Islamic terrorists are daring the Russian government to get into a pitched battle with them — and they have succeeded by killing its ambassador to Turkey. The shooting was an act of war — a public statement of enmity, a challenge. Putin will almost certainly not back down from the punch in the gut. The terrorists are foolhardy in their belligerence. They blow themselves up in an effort to kill others. They kill indiscriminately. They rape and pillage and justify all of their actions in the Koran. Peace-loving Muslims are horrified, but there is little they can do other than to cooperate with authorities in isolating radicals and turning them in. The more that acts like this happen, the greater the burden on Islamists to prove they belong in the 21st Century and are not throwbacks to AD 700. The communications gap is growing by day, and there is an urgency to stop its growth and close it.