There is a real and valid reason for islamophobia. That reason can be traced back to 622 AD and the first jihadi warriors.
Between 622 AD and about 1760 AD, more than one thousand years, Muslim warriors waged vicious battle against the people of the Middle East, North Africa, and Europe. The lowest estimate of non-Muslim deaths is 140,000,000 while some have estimated it closer to 300,000,000. That works out to between 1,400,000 to 3,000,000 deaths per year. In contrast, the Holocaust of Nazi Germany seems small.
Who wouldn't be afraid of something like that happening again?
True, since 1760 Islam has become more moderate. After the Muslim alliance with the Germans in both world wars, their influence was dealt a severe blow. It is little wonder they resent the establishment of Israel in their midst, a constant reminder of that defeat and subjugation of their power. That resentment has festered for decades, constantly stirred and revived by a fringe radical element, a resentment that threatens to once more burst into full flame just as the German resentment of the Treaty of Versailles led to the rise of the Third Reich.
Comparison of the current atrocities to the Crusades are based on incorrect information, propaganda, and outright lies. The truth would never support that comparison.
When the facts are examined dispassionately, disregarding agenda and political spin, we can see that the spread of Islam has a bloody and violent history. Recent events in Scandinavia, Europe, the Middle East, North Africa, Southeast Asia, the Pacific Islands, and even Australia show that the new jihadi movement has ambitions far beyond its predecessor. This new movement aims to establish a global caliphate using any means possible: military, economic, social, legal. No longer is the tool of Islamic radicalism merely the sword. It is now the media, terror, and conversion of the population through increased birthrate.
Islam intents to outearn, outspend, outfight, and outlive all other faiths. Muslim radicals are in it for the long term. After all, they've been at it for 1400 years.
What's another millennium? or two?