"TENS OF thousands of children unaccompanied by parents or relatives are flooding across the southern U.S. border illegally," Reuters reported, "forcing the Obama administration and Congress to grapple with both a humanitarian crisis and a budget dilemma."

Read that again, the part about "unaccompanied by parents or relatives." By "children" Reuters means under the age of 18, some are as young as 3. In Wednesday Senate testimony, Homeland Security Secretary Jeh Johnson said "an overwhelming number" were under 12.

President Obama calls it a humanitarian crisis.

After a decrease in illegal immigration when the U.S. economy tanked, it's back with a vengeance, in a troubling form.

An estimated 60,000 minors will pour in this year, up from an estimated 6,000 in 2011, according to the administration. It's believed 130,000 minors will arrive in 2015 (in addition to the adults) costing U.S. taxpayers $2 billion.

Detaining an apprehended child costs $252 a day.

Read that again, $252 a day to detain a child in a shelter, foster home or military base. That includes shelter, food, clothing, education and entertainment. The cost is stupefying.

Wouldn't you like to have 252 government dollars a day for your child? The average time in the program is 35 days, according to Health and Human Services. I called the government to ask for a cost breakdown of the $252. The government didn't respond.

Several theories seek to explain the youth surge.

*  The children are escaping violence - domestic abuse or gang recruitment - in their homelands, mostly Honduras, El Salvador and Guatemala.

*  Border apprehensions were at historic lows, according to U.S. Customs and Border Protection. Lax enforcement encourages minors to try their luck at getting in. The worst that can happen is they get sent back - eventually - to try again.

Actually, the worst that can happen is rape, beating, robbery or death at the hands of "coyotes," criminals who traffic in humans and help them cross the border.

* Central Americans misunderstood President Obama's executive order to prohibit deportation of minors and called in the kids. (Obama's action does not protect recent arrivals.)

After children are captured, within 72 hours they must be turned over to HHS, which protects them. Their vast numbers have overwhelmed the system.

If these children are truly fleeing danger, they are in a different category than others who crash the border. Immigration law defines a refugee as someone who demonstrates they fear persecution due to race, religion, nationality, political opinion or membership in a particular social group.

If truly threatened, the U.S. has a moral obligation to fulfill its humanitarian impulse and accept them. We can ask our neighbors also to accept them. (Rather than help, Mexico permits a conduit from Central America to El Norte.) Perhaps the United Nations can help settle them elsewhere. We should be a lifeboat, but not the only lifeboat.

One question: Are circumstances so much more dire today than two years ago - or have the kids and their parents learned that asking for sanctuary is the soft underbelly of American law? They get free room and board followed perhaps by reunification with a parent (who may be here illegally).

Most of the kids cross the border and promptly "surrender" to the nearest Border Patrol agent.

"They know they have nothing to fear," says Shawn Moran, vice president of the National Border Patrol Council, the agents' union.

This crisis connects with immigration reform. A majority of Americans want that, as long as it is not "amnesty," which a majority opposes.

Republicans will endorse reform only if it is amnesty-free and only if it guarantees strong enforcement at the border.

If we don't seal the border this mess will only accelerate.

The reality is we won't let kids starve, but we shouldn't be bamboozled into admitting them without proof they are in danger. These are foreign nationals and their own governments have obligations, too.

Email: stubyko@phillynews.com

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