Every once in a while something really big happens, but the true impact isn’t felt until years down the road.

For example, I’m sure that John Montagu, the fourth Earl of Sandwich, had no idea that he would change the way the world ate lunch the day that he had a hankering for some meat between a couple of slices of bread while gambling.

President Obama also probably didn’t understand the trouble he would cause by mocking Donald Trump at the 2011 White House Correspondents’ Dinner.

Yada, yada, yada … America is great again.

And most importantly, few people knew in 2005 when the Service Employees International Union decided to break away from the AFL-CIO, mostly over the issue of immigration, the debate over the border would be changed forever.

Prior to this split, trade unions were largely against open borders. They figured that bringing in an influx of cheaper workers would break unions and drive down wages.

It wasn’t even just the manufacturing trades who felt this way — Cesar Chavez of the United Farm Workers of America also took a hard-line against illegal immigration.

Elected Democrats generally parroted what their benefactors in organized labor were saying — and in many cases went even farther — also condemning the strain on public resources associated with uncontrolled immigration.

In 1993, Sen. Harry Reid, D-Nev., took to the Senate floor and called on President Clinton to end “insane” birthright citizenship, clamp down on asylum seekers and deport criminal aliens.

Related Articles Proposition 15 will hurt homeowners, too

Donald Trump versus the military-industrial complex

Don’t lose sight of the progress made, problems ahead: Walter Williams

Papering over the stream of bad news

Hold off on Ruth Bader Ginsburg replacement: Tom Campbell “Our federal wallet is stretched to the limit by illegal aliens getting welfare, food stamps, medical care and other benefits often without paying any taxes. Safeguards like welfare and free medical care are in place to boost Americans in need of short-term assistance. These programs were not meant to entice freeloaders and scam artists from around the world,” Reid said.

The Nevada Democrat went on to say, “If making it easy to be an illegal alien is not enough, how about offering a reward for being an illegal immigrant? No sane country would do that, right? Guess again. If you break our laws by entering this country without permission and give birth to a child, we reward that child with U.S. citizenship and guarantee full access to all public and social services this society provides. And that is a lot of services. Is it any wonder that two-thirds of the babies born at taxpayer expense in county-run hospitals in Los Angeles are born to illegal alien mothers?”

California Sen. Dianne Feinstein also sounded quite Trumpian. On a 1994 edition of CBS’ Face the Nation, the California Democrat declared “Border control is a federal responsibility. We simply don’t enforce our borders adequately. In my state you have about 2,000 people a day, illegally, who cross the border. Now, this adds up to about two million people who compete for housing, who compete for classroom space. We’ve had a Medicaid situation, where in 1988 there were about 3,000 people on Medicaid, there are now well over 300,000 people on Medicaid today, who are illegal aliens. That presents obvious problems.”

Even President Clinton got in on the action. In his 1995 State of the Union Address, Clinton stated, “All Americans, not only in the states most heavily affected but in every place in this country, are rightly disturbed by the large numbers of illegal aliens entering our country … The jobs they hold might otherwise be held by citizens or legal immigrants. The public service they use impose burdens on our taxpayers.”

Then in the 2000’s, all of the power in organized labor shifted from manufacturing to the service and public sectors, and suddenly the SEIU started calling all the shots.

The new bosses immediately put the word out that they wanted open borders. Elected Democrats “evolved” on the subject overnight and declared that anybody who didn’t get the memo lives in a basket with other deplorables!

Since Democrats have convinced themselves they only lost the once reliably blue Rust Belt states of Pennsylvania, Michigan and Wisconsin because Vladimir Putin rigged the election, they thought it would be a grand idea to shut the government down in the name of illegal immigrants!

As I said before, sometimes when something big happens, it can take a while to figure out just how important it really was, but even years later, some people never manage to figure it out.

John Phillips is a CNN political commentator and can be heard weekdays at 3 p.m. on “The Drive Home with Jillian Barberie and John Phillips” on KABC/AM 790.