In politics, you fight over what matters. The more something matters, the bigger the fight. Since President Franklin Roosevelt in the 1930s, the Supreme Court has mattered — today more than ever.

For the first 150 years of our nation’s existence, most of the power resided in either the Congress or the presidency. Then, with Roosevelt and the New Deal, the Supreme Court became a fulcrum of power which has been growing ever since.

The “New Deal” changed the nature of government forever. Prior to Roosevelt’s legislative agenda, Presidents Calvin Coolidge and Herbert Hoover presided over budgets of less than the equivalent of $45 billion today. Our current federal budget is $4 trillion, and it never could have grown so large without Roosevelt’s New Deal programs and the expansion of legislative power. There would have been no New Deal without the approval of the Supreme Court.

Many forget that the first New Deal was struck down by the Supreme Court. Its big government programs and market interventions were declared unconstitutional. Unwilling to comply with the Constitution and emboldened by election victories, Roosevelt openly mocked the Supreme Court, threatened to pack it with liberals, and ultimately bullied it into submission.

In the end, he got his way, and the Second New Deal was enacted.

Roosevelt didn’t just bully the Supreme Court — he also rallied Americans to his cause by attacking the power of the Constitution, the Founders, and the sitting Supreme Court. Read his words given on Sept. 17, 1937, on Constitution Day no less, when he had the nerve to say this about our Founders:

“The men who wrote the Constitution were the men who fought the Revolution. They had watched a weak emergency government almost lose the war, and continue economic distress among 13 little republics, at peace but without effective national government . . . Madison, most responsible for it, was not a lawyer; nor was Washington or Franklin, whose sense of the give-and-take of life had kept the Convention together.”

In other words, however successful, the Founders were not experts in government.

As for the Constitution, Roosevelt said that it “was a layman's document, not a lawyer's contract. That cannot be stressed too often.” This was another dig at the Founders which laid the groundwork for the argument that the document was pliable.

He went on to say:

“When [the Founders] considered the fundamental powers of the new national government they used generality, implication and statement of mere objectives, as intentional phrases which flexible statesmanship of the future, within the Constitution, could adapt to time and circumstance.”

He wasn’t finished, though. As to the sitting Supreme Court justices who turned down the New Deal, he cried, “We cannot seriously be alarmed when they cry ‘unconstitutional’ at every effort to better the condition of our people.”

Get the picture? Yes, the Founders were successful and fought a revolution. But let’s not get too carried away by revering them. The document is good, but it’s not a contract. Indeed, it is just a document that should be adapted to “time and circumstance.”

Sound familiar? The Democrats have been saying that to one degree or another for the last 80 years — and quite successfully, I might add. Along the way they picked up huge victories in cases like Griswold v. Connecticut in 1965 which created a "right to marital privacy," Roe v. Wade in 1973 on abortion, and Obergefell v. Hodges in 2015 on same-sex marriage — a decision authored by retired Justice Anthony Kennedy, the man Justice Brett Kavanaugh replaced.

Democrats have used the court system over and over again to get victories they couldn’t get in the state legislatures or from voters. Those three mentioned cases are a subset among those victories.

In the past, when Democrats’ ability to use the courts was in doubt, the Left would rise up in defense. So, when the conservative Clarence Thomas was proposed to replace the liberal Thurgood Marshall, an awful, divisive fight ensued in 1991. Prior to that, when President Ronald Reagan nominated the conservative Robert Bork to replace Justice Lewis Powell, who had voted for Roe v. Wade, the fight was on. The New York Times noted that “the No. 2 Democrat in the Senate, Alan Cranston of California, the party whip, urged colleagues in a letter to form a 'solid phalanx' of opposition if the President's nominee was an ideological extremist.”

Sound familiar? There are brutal fights when liberal justices retire.

That is very unsettling for the Left, but not the worst possibility — God forbid any of the remaining four liberal justices have to replaced. That would mean the loss of the Supreme Court for the Left, something they have coveted for eight decades and likely will do “anything,” as Sen. Chuck Schumer, D-N.Y., said, to protect.

Of course, all of that points to just how important it is to be the party in control of the Senate. The November midterms will be the next installment of that competition.

Thomas Del Beccaro (@tomdelbeccaro) is former chairman of the California Republican Party and author of That Divided Era: How We Got Here and the Keys to America's Reconciliation.