The death of Supreme Court Justice Antonin Scalia doesn’t merely mark a tragedy for Constitutional philosophy – it may mark the death of American Constitutionalism as a whole.

Scalia’s philosophy of jurisprudence is well-known and shaped two generations of conservative thinkers: the Constitution ought to be interpreted according to its original meaning. This shouldn’t have been a groundbreaking notion given that most legislation is interpreted according to those rules, but because leftist jurists have spent a century chiseling away at the meaning of the Constitution based on their personal political beliefs, Scalia’s reinvigoration of traditional interpretive methodologies made him a historic figure. Scalia’s brilliant, passionate writing style made him author of some of the most famous dissents in Supreme Court history, and channeled the modern conservative frustration with the continuing abandonment of the Constitution.

Scalia’s jurisprudence also reminded conservatives that there is no substitute for proven Constitutional originalism. Most conservatives ignored that when they greenlit the appointment of cipher John Roberts for Chief Justice of the Supreme Court, a point I made when he was appointed. But Scalia provided a consistent reminder that Constitutional philosophy matters. It isn’t just a game of doing whatever you want politically. Constitutional jurisprudence is about recognizing the limits of the federal government – and recognizing the limits of the politicization of the Court itself.

In the end, Scalia’s death could mark the end of the Constitution itself. That’s because the current Supreme Court rested, until Scalia’s death, on the vague, confused, indeterminate philosophy of Justice Anthony Kennedy, who apparently decides cases on the basis of whether he has a solid bowel movement that morning. That means that half the time, the Constitution has a shot, as in Citizens United; the other half of the time, the Constitution drains away into the mists of Kennedy’s magical social justice thinking, as in Obergefell.

Unlike Kennedy, Scalia represented a consistent vote for a Constitution beyond modern progressive power politics. But with his death, President Obama now has the power to appoint a fifth justice to join hard-left social engineers Elena Kagan, Sonia Sotomayor, Stephen Breyer, and Ruth Bader Ginsburg. If the Republican Senate allows President Obama to select Scalia’s successor, the left will have a complete monopoly on the Supreme Court. Within the next few years, Citizens United will be overturned, restoring limits on free speech; the Supreme Court will render the Second Amendment meaningless by reinterpreting the right to bear arms as a non-personal right; freedom of religion will be made subservient to same-sex marriage and abortion priorities; the death penalty will be ruled unconstitutional; unions will be allowed to continue confiscating the dollars of people who disagree with them politically; redistricting along leftist lines will return. Scalia ensured that the Supreme Court wasn’t a transformative institution; now it will become the chief tool in the left’s arsenal.

It’s a sad commentary on the state of conservative politics that the only thing standing between the United States and the death of its founding document was a brilliant 79-year-old jurist. But unless Republicans stand up on their hind legs now, that will certainly be the case.

Ben Shapiro is Senior Editor-At-Large of Breitbart News, Editor-in-Chief of DailyWire.com, and The New York Times bestselling author, most recently, of the book, The People vs. Barack Obama: The Criminal Case Against The Obama Administration (Threshold Editions, June 10, 2014). Follow Ben Shapiro on Twitter @benshapiro.