The popular resistance in the West to accepting Moslem refugees is based on the fact that this will increase the number of Islamic terrorists in the West. That has already been proven, but not because Islamic terrorists are trying to get into the West by pretending to be refugees fleeing Islamic terrorism. No, it is worse than that. For a decade opinion polls of Moslems living in the West indicated that, overall, these Moslems were getting less enthusiastic about Islamic terrorism. Yet despite the majority (sometimes over 80 percent, as it is in the United States) of Moslems opposing Islamic terrorism a small percentage believe such violence is justified. Typically ten percent or more of Western Moslems believe suicide bombing, and similar violence against civilians can sometimes be justified to defend Islam. Even more Western Moslems report witnessing other Moslems expressing, or calling for, support of Islamic radicalism. Yet the majority of Western Moslems, especially those in the United States, are concerned about the rise of Islamic radicalism among Moslems in the West.
Moslems often stress that attacks that are "justified" mainly because of Israel. Moslem media and politicians have been preaching virulent anti-Semitism for over a century now, and it only got worse when Israel was established sixty years ago. This is pretty nasty stuff, and you can pick it up on al Jazeera or the Internet, although the worst of it is only available on Arab language sites. Al Qaeda, which originally did not see Israel as a primary target, eventually changed its mind and found that Moslems conditioned to hate Israel can be converted into general purpose Islamic terrorists. This anti-Semitism often expresses itself in the form of physical assaults on Jews or damage to Jewish religious or educational buildings in the West. This makes it easier to convert and radicalize non-Moslems in the West. There are not a lot of these murderous converts but they get a lot of media attention. Less well publicized is the larger number of children or grandchildren of Moslem migrants who are radicalized in the name of religion and attracted to risking their lives in a holy war against non-Moslems. This is not a unique situation now or historically but it is more common among Moslem populations.
There are about 25 million Moslems in the West, most of them in Europe. American Moslems are much more successful economically, and optimistic about living in a non-Moslem culture, than their more numerous European counterparts. The European Moslems are about twice as likely to justify terrorist acts. European Moslems are much less optimistic about their prospects in a non-Moslem culture. For that reason, Islamic leaders who back an Islamic takeover of Europe are quite popular over there.
Countries with higher percentages of Moslems also tend to have a higher proportion of people in favor of Islamic terrorism. There, the main reason for such violence is the "defense of Islam." Despite the fact that Moslems are attacking non-Moslems all over the world, Moslem media and politicians get away with proclaiming that Islam is "under attack." This accusation is hardly recognized in the West, which is supposed to be the chief aggressor. But in the Moslem media, there are endless screeds calling on Moslems to help defend Islam. How can this be? A lot of it has to do with cultural attitudes towards logic and fantasy. Even in the United States, you have a lot of people who believe in conspiracy theories, including ones about the 911 attacks being a plot by the U.S. government to get the nation into a war. This is believed by a majority of people in some Moslem majority nations, and a quarter of U.S. Moslems, do not believe that Arabs were responsible for the 911 attacks, despite forensic evidence, and al Qaeda leaders bragging about it on videos.
While many Europeans believed Islamic terrorism in their midst was caused by the American invasion of Iraq, the local police knew better. Islamic terrorism has been a problem in Europe for over three decades, and in the 1990s it was getting worse. After September 11, 2001, and especially after the 2003 invasion of Iraq, it was fashionable for more Moslems, especially young ones, to declare America an "enemy of Islam."
More thoughtful Moslems realized that the Islamic terrorists were screwing up things for everyone. All Moslems were now tainted. Sure enough, the Islamic terrorists soon began killing Moslems in Moslem countries. This was nothing new for most Moslems, because this kind of terrorism had been going on for over a decade before 2001. Egypt, Algeria, Pakistan and Afghanistan were all suffering from Moslem-on-Moslem violence in the 1990s. All in the name of religion.
In Europe the Moslem populations were often allowed to exist as a very foreign presence. Sort of ethnic enclaves, and within these areas Islamic radicalism flourished. There were only a few terrorist attacks, and it was only because the security forces hustled that there weren't more. While (most of) the politicians continued to preach ethnic diversity, they were told by their security people that over one percent of their Moslems were willing to get involved in terrorist activities, and that there were thousands of European Moslems that needed to be watched. These included Islamic radicals who had fled the United States, or the Middle East. Europe was a convenient place for Islamic radicals to hide out. The social welfare benefits were excellent. If an Islamic radical could afford it, his wife (or wives) and kids could be brought in, and the European governments would take care of them. However, after September 11, 2001, it was no longer easy to get in as a political refugee. But there were professional people-smugglers who, for a fee, could get just about anyone into Europe. The smugglers are still doing big business bringing Moslem refugees, and the increased risk of Islamic terrorism, in to the West.