The religion of peace has stuck again.

Last week it was Brussels, but it is too late to guard our gates, as brave Horatius lamented:

Then out spake brave Horatius, The Captain of the gate: “To every man upon this earth Death cometh soon or late. And how can man die better Than facing fearful odds For the ashes of his fathers And the temples of his gods.”

As the FBI well knows, ISIS is already inside the United States. Guarding our gates is still necessary, but it is not enough when thousands of Islamist jihadists are already here — and being aided by Muslims attending a friendly neighborhood mosque near you.

The unpleasant, politically incorrect truth is that ISIS is only the point of the spear, the jihadist with the suicide belt and the duffle bag bomb, but that messenger was sent by Islam itself.

In Brussels, police have said that some of the murderers who carried out the Paris attacks were hidden and aided for months by the Muslim communities in Brussels. ISIS “cells” cannot survive and build their bombs and conduct their attacks without help from a broader network of sympathizers.

After each terrorist attack carried out by Islamist militants, we are told that the religion of Islam is blameless and we are lectured and warned against the evils of “Islamophobia.” No one is permitted by the PC police to hold the “religion of peace” and its mosques and imams accountable for crimes committed for the greater glory of Allah.

To the American left and its willing collaborators in the media and the halls of power, “Islamophobia” seems a greater threat than ISIS. This moral confusion violates Sun Tzu’s first principle of warfare: know thy enemy. Effective war planning and countermeasures are impossible if you are more concerned with political correctness than defeating the enemy.

Common sense says don’t let the enemy inside the gate. Political correctness says put out the welcome mat.

The evidence of collective insanity is all around us. Is it any wonder citizens are rebelling against the establishment when willful blindness is praised as a humanitarian virtue?

Our political establishment, including the business community, continues to tolerate and excuse open borders despite overwhelming public support for halting all illegal entry.

Our leaders continue to import new Islamist refugees from Syria — adding to the half-million already here from Somalia and other Muslim nations — despite ISIS’s documented success in infiltrating its trained jihadists among those refugees.

Our leaders and our media continue to criticize growing European efforts to curtail the movement of over two million Muslim “refugees” into Europe despite the cultural conflict accompanying that chaotic movement.

Our limited military action against ISIS strongholds in Iraq and Syria is designed to silence domestic critics, not to destroy ISIS. Killing ISIS’s top commanders one by one is like killing cancer cells one by one.

It’s bad enough that this idiotic code of silence is enforced by the mainstream media, the universities, and the Obama administration, but it is nothing but sheer stupidity wrapped in cowardice when Republican leaders and conservative pundits fall into line and censor themselves.

It is not “radical Islam” that has declared war on us, it is orthodox Islam as defined and taught in Islam’s holiest texts, the Quran and the Hadith.

What Obama insists on calling “extremists” or “radicals” are Muslims who are devout in their adherence to Islam’s doctrines.

“Moderate Muslims” are the less devout who do not follow Islam’s teachings

It is Islam’s basic worldview that inspires hatred of the West, not grievances against U.S. foreign policy or lack of economic opportunity in Muslim societies.

The Muslim Brotherhood was founded in 1928, not 1988, decades before any American soldier set foot in Kuwait.

Why then is it “Islamophobic” to speak the truth about Islam’s hostility to Western values? Self-censorship is the main obstacle to effective steps to halt ISIS in its tracks, and people who preach such nonsense — and the Quislings who tolerate it — are aiding ISIS and need to be called out for it.

It is well known that the FBI has over 900 active investigations underway of ISIS sympathizers in every state, and it is only the lack of manpower that limits that number.

Yet the leftist Mayor of New York City has dismantled a surveillance program aimed at radical mosques and Islamist organizations– all in the name of preserving civil liberties– and such moral idiocy is applauded.

Meanwhile, tens of thousands of Somali-born migrants living in towns in Minnesota, Texas and California are demanding their own courts, their own schools, and are electing their own mayors — as well as sending young men to Syria to be trained as ISIS warriors.

And what is the response of our government? the Obama State Department wants to bring MORE Somali and Syrian refugees, and the Republican Congress refuses to halt the insanity.

What is the source of this willful blindness? To say it is political correctness run amok only raises the question, why the popularity of policies that are so obviously suicidal?

Our future safety and security depends on waking up from a suicidal expansion of Islamic communities inside our country. Until we do that, doubling or tripling the number of air strikes against ISIS enclaves 6,000 miles away is whistling past the graveyard.