The U.S. has lost track of 6,000 students, and hidden tens of thousands of minors.

Thomas Jefferson once said, “A country with no border is not a country.” It was true wisdom.

In the 1950s the United States had an immigration policy that maintained national security and unity in a country of peoples with hundreds of different nationalities, races and ethnicities. The system did largely favor immigrants of Western nations, but a nation has an absolute right to decide who immigrates within its borders. If citizens want to change immigration policy, so be it. But what citizens want and what they get are two very different things in Washington, DC.

In 1965 Ted Kennedy arose to do the Democrat thing and fundamentally transform America with his proposed immigration bill. He denied his intentions vigorously: “Under the proposed bill, the present level of immigration remains substantially the same. … [T]he bill will not inundate America with immigrants from any one country or area. … [The] ethnic pattern of immigration is not expected to change as sharply as critics think.”

That bill became the first in a series of immigration “reform” bills that passed and gave us our present rancorous multicultural society.

Sixty-five years later, with a population far more than “substantially” changed, we face critical, urgent problems caused by unrestrained immigration that must be solved soon if we are to remain a nation. We offer two examples.

First, even after the lessons of 9/11, government has failed to sufficiently track student visas, and some recipients simply disappear before or after their visas expire. Last year alone 58,000 failed to leave when required, and of that group, U.S. Immigration and Customs Enforcement (ICE) is trying to find 6,000 considered to be of “heightened concern.”

Between 2003 and 2012 the number of students on visas nearly doubled, climbing from 663,000 to 1.2 million. It now exceeds a million per year. And virtually any kind of school qualifies: beauty school, massage school and, yes, flight school, a third of which have no FAA certification.

One school with four campuses remains in operation even though five top executives have been indicted for visa fraud. The indictment charges that 80% of enrolled foreign students had delinquent attendance, which the school failed to report. The execs pled not guilty.

The ICE official in charge of investigating student visa violations said ICE has no choice but to allow the school to continue facilitating student visas, explaining, “[T]his is the United States of America and everyone has due process.”

Second, where are the thousands of illegal alien children who continue entering our country? Some in the government know, but ABC News could not get an answer. The Department of Health and Human Services website says, “We cannot release information about individual children that could compromise the child’s location or identity.”

Not compromising illegal aliens’ identity now takes precedence over not compromising national security. Remember, many of those “children” are in their late teens or early 20s. Some belong to either of the two most dangerous Latino gangs that have been recruiting heavily at detention centers. Plus there’s no way of knowing how many terrorists have infiltrated our nation after Barack Obama’s emasculation of the Border Patrol and the laughable performance of ICE.

Reportedly, more than 100 shelters are spread throughout the country to house children, and more are going up. Additionally, more than 37,000 children have been released to relatives or sponsors. How many of the relatives are here illegally themselves?

One private social welfare organization refused $50 million for housing children to avoid “negative backlash.” Sen. Charles Grassley (R-IA) did the math, and it comes to a cool $166,000 annually per child.

Even members of Congress can’t get information out of the administration, a typical Obama game.

Bottom line: Wherever these kids land, local costs rise immensely. By law they are entitled to health and social services as well as education, meaning bursting hospitals, welfare rolls and classrooms. Adding kids who can’t speak English, and are probably illiterate in their own language, will require more specialized teachers. It’s too bad the full costs won’t hit before November.

Finally, what’s going on at the border now? Certainly the influx of illegals hasn’t ended, but ISIL beheadings and Vladimir Putin’s adventures are front page now. The alien invasion is old news.

We’ve seen much of what Obama meant by “fundamentally transforming” America, but with almost two-and-a-half years remaining in his presidency, it looks like we ain’t seen nothing yet.