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Enough.

More attacks, more carnage, more death -- this time in Brussels, Belgium. After the Charlie Hebdo attack, the social media hashtag was "Je Suis Charlie Hebdo." After the Bataclan attacks in Paris, it was "Pray for Paris." Now it is "Nous Sommes Bruxelles" ("We are Brussels").

No, we're not. But we will be, unless steps are taken to prevent any more attacks.

We are hearing the usual platitudes from President Obama and others: "We will not be defeated." "We will conquer terror." There is zero political will behind these statements. If there were, you would see immediate efforts to prevent -- at the very least -- immigration from countries that spawn terrorists and sponsor terror. You can no more "conquer terror" by letting terrorists into your country than you can prevent theft by letting thieves into your home.

It is time to close our borders. It is time for a temporary moratorium on immigration.

In fact, it is past time. We have been amply warned. Brussels was hit this week. Paris was hit in January and again in November of last year. The United States suffered terrorist attacks in San Bernardino last year, at the Boston Marathon in 2013, at Fort Hood in 2009, and of course, in New York City on Sept. 11, 2001. (In fact, if you want to see something truly sobering, check out the Wikipedia page titled, "List of Islamist Terrorist Attacks." Pay attention to the escalation -- from a handful of incidents in the 1970s to nearly an attack a day somewhere in the world in 2015. Even assuming that contemporary record-keeping is more thorough, the numbers are staggering.)

In addition to the planned terrorist attacks, Europe is dealing with widespread crimes committed disproportionately by migrants, including hundreds of incidents of sexual assault in Germany and Sweden, theft and other property crimes, and even murder.

Our situation in the United States is not much better. With our own porous borders, over 100,000 illegal immigrants cross into the United States each year. In 2014, nearly 10,000 unaccompanied children from Mexico and Central America crossed the border every month.

Are we sending them back? Nope. Are we sending back those who commit crimes? Not with any consistency. Also in 2014, according to testimony before the Senate Judiciary Committee, the Obama administration released "193 illegal immigrants with homicide convictions, 426 people with sexual-assault convictions and 16,000 with drunk-driving convictions." Over the past three years, more than 100,000 illegal aliens who have been convicted of crimes and who should have been deported have been released by the Obama administration back into the general population.

Some who have been deported return to commit additional crimes with impunity. Last year, 32-year-old Kate Steinle was killed in San Francisco. The man accused of her murder, Juan Francisco Lopez-Sanchez, has seven previously felony convictions and had been deported five times. San Francisco refused to turn him over to federal authorities, pursuant to its "sanctuary city" policy.

Just last week, in Framingham, Massachusetts, a woman was gang-raped and her boyfriend beaten by four illegal immigrants from Guatemala. Two of the accused attackers had been previously deported, one for drunken driving and disorderly conduct. They managed to make their way back to the U.S.

Meanwhile, the Obama administration cuts aerial surveillance at the border by 50 percent, and our border patrol agents say that they are being instructed not to enforce immigration laws.

Why are we putting up with this?

It's not possible to read a conservative publication without hearing the mewling and whining of the "NeverTrumps." Do you want to know why Donald Trump is walking away with the Republican nomination? This is why.

And all of you -- including President Obama -- who are so sure that Hillary Clinton will beat Trump in a walk? Don't be so sure. Clinton just announced that she wants to extend Obamacare benefit to illegal aliens. How convenient! If they're injured assaulting American citizens, their health care will be paid for -- by those of us who are still working.

I'm well aware of the objections to a moratorium on immigration. There are those who will say, "You are punishing those who did nothing wrong." To that I reply, don't blame us; blame those who have exploited our generosity and our liberty.

And some will argue (as they always do), "If we close our doors, then the terrorists have won."

Wrong.

If we leave our doors open, then the terrorists win. If we allow people to pour across our borders, then the terrorists win. If we refuse to do meaningful background checks, then the terrorists win. If, knowing -- as we do -- that our current practices create an increased risk of attacks and mayhem and destruction and death, we do not change those practices, then the terrorists win.

Because they will know that they can do what they like; that they can disrupt our lives and slaughter our citizens, and nothing will change.

It is an election year. Here is my take on things: The decision to place a moratorium on immigration sends the message that protecting American citizens and lawful residents is more important than whatever benefits might be obtained by an open-borders policy.

Any candidate who cannot or will not make the public statement that protecting America's citizens and lawful residents is his or her single most important priority does not deserve to hold public office.

And probably will not get the presidency.