Islam makes its presence in America felt in many ways. Sometimes it happens through violence. Far more often it happens when Muslim immigrants arrive and plant their own institutions and customs on American soil. And some Muslims come with the specific purpose of spreading Islam.

There are now roughly 3,200 mosques in America, nearly three times as many as there were in 2000. And these are not just any mosques, according to Leo Hohmann, a WND news editor who has reported extensively on Islam and immigration.

"A lot of these mosques that we have in this country are more radical than what you would find even in the Middle East: 85 percent of the imams in this country are foreign-born, getting their education from Al-Azhar University in Cairo, or another major university in Saudi Arabia," Hohmann said during a recent appearance on "Caravan to Midnight" with John B. Wells.

Hohmann, who authored the book "Stealth Invasion: Muslim Conquest Through Immigration and the Resettlement Jihad," said many of these imams come to the U.S. on R-1 visas, which are for ministers and other religious workers.

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"These are the worst of the worst," he declared. "These are the people that really are serious about spreading Islam, and they're using our visa system and the ignorant, naïve American kafir to come in here and spread it."

What's more, Hohmann pointed out that roughly 80 percent of American mosques are funded at least partially by Saudi Arabia, home of the radical Wahhabi strain of Islam.

"These are not just your average imams," Hohmann warned. "They're the ones wanting to come into the belly of the beast, so to speak, the infidels' territory, and spread their form of Salafist, often Wahhabist Islam, and it's a real problem. We need to clean up this visa system."

Some Americans concern themselves with militant Islamists – those who would take up arms against America if called upon by a preacher. While this is a problem, Hohmann estimates they make up only a small fraction of the U.S. Muslim population. To him, the bigger problem is the long-term threat of civilization jihad, in which Muslims take advantage of the liberal U.S. immigration system to settle in America and build up a parallel society within a society.

There are many types of visas they can and do exploit to enter the country: religious worker visas, fiancé visas, other family-based visas, entrepreneur visas, student visas and many more. Hohmann said there is little to no vetting in many of these visa programs. At some point, the numbers of immigrants start to add up.

"To me, the bigger problem is if this continues to build like this, before long – we see this happening in Europe already – the numbers get to a sort of critical mass where the danger increases exponentially," he warned. "And what I mean by that is not just of violence or violent jihad, but civilizational jihad where you see more and more demands coming from the Muslim population on the non-Muslim population. We've already seen the first dribblings of it here in the United States. They come here and it seems like – I call them in my book 'super-citizens' because it seems like they get more rights and privileges than regular citizens."

America is headed down a suicidal path – but it's a subtle invasion, and not many Americans understand the full extent of the problem. Get all the details in Leo Hohmann's new book "Stealth Invasion: Muslim Conquest Through Immigration and Resettlement Jihad," available now in hard copy or e-book at the WND Superstore.

He explained how it usually works, using colleges as an example: Young Muslims arrive from the Middle East on student visas. They join the Muslim Student Association, which is a Muslim Brotherhood front group, or if their campus doesn't have an MSA chapter, they form one. Then they use the MSA as a platform to agitate on campus for various special rights and privileges.

He said the University of Kansas, at the insistence of MSA leaders, has set up a special lunchroom for female Muslim students, many of whom come from Saudi Arabia.

"These folks coming in from Saudi Arabia are dressing themselves in burqas and niqabs, the women, and they sit in the lunchroom of the university and they say that it's very uncomfortable for them to eat their lunch in the regular lunchroom," Hohmann said. "Why? Because they have to pull their niqab or burqa up and try to funnel the food up under the veil, because they can't take off the veil and God forbid some men in the lunchroom might see their face."

So the university gave the veiled Muslim women their own lunchroom where they could take off their facial coverings and eat their lunch without any men seeing their faces.

Hohmann added many public schools have set aside prayer rooms for Muslims only and/or ritualistic footbaths for their Muslim students. He sees all of this as evidence that American institutions are moving away from the concept of assimilation and towards the concept of integration. There is a subtle but important difference between integration and assimilation.

"Inherent in that term [integration] is a subtle twisting of what we expect of our immigrants," he explained. "When we asked them to assimilate, they had to adapt to our culture, but when we integrate them, we flip it around, and we place the burden on the host society, us, to accommodate the immigrant. It's flipped around. We no longer expect them to adopt our ways; we adopt their ways and their culture, and that's why you see schools, universities, police departments bending over backwards to accommodate these Muslim immigrants."

To Hohmann, rampant immigration without assimilation qualifies as an invasion. He wonders when Americans will finally stand up and resist the invasion.

"At what point do we become willing to defend our way of life and our culture against this other competing system that we've invited in?" he asked. “These people are here at the invitation of the U.S. government. It's legal immigration. But at what point do we say these folks really don't value what we value?"

Hohmann believes it's important to not only resist Islamic culture, but to preserve America's Christian culture, which he thinks is the best bulwark against Islam.

"In my opinion, societies are going to have some sort of religion, and if it's atheism and hatred for Christianity, then you're just opening the door for Islam, and that's what we saw happen in Europe," he cautioned.

Hohmann knows it's unpopular, even among some conservatives, to oppose unfettered legal immigration. But he encourages all concerned Americans to persevere no matter what insults the critics may hurl their way.

"We have to expect to be called names," he said. "We can't be afraid of name-calling. They will call you these vicious names because that's really all they have. They don't want to debate the facts. So I would just suggest that we remain vocal, remain unafraid, because if we're afraid then we have already granted them the victory because that's what they want. They want us to be afraid and they want us to shut up."

America is headed down a suicidal path – but it's a subtle invasion, and not many Americans understand the full extent of the problem. Get all the details in Leo Hohmann's brand new book "Stealth Invasion: Muslim Conquest Through Immigration and Resettlement Jihad," available now in hard copy or e-book at the WND Superstore.