Chris W. Cox is executive director of the National Rifle Association’s Institute for Legislative Action.

Last month, Second Amendment advocates and other patriotic Americans were shocked by the news of the sudden passing of Supreme Court Justice Antonin Scalia. His death was a tragedy for our Constitution and our country. For supporters of the Second Amendment, his death could result in the end of individual gun ownership in the United States.

In 2008, the Supreme Court answered the question of whether individual citizens have a right to own a firearm in their homes for self-defense. It was Scalia who wrote the majority opinion in that case, District of Columbia v. Heller. That landmark decision made clear that the Second Amendment guarantees an individual right to keep and bear arms. Shockingly, the decision was only 5 to 4. Two years later, in McDonald v. Chicago, Scalia joined Justice Samuel A. Alito Jr.’s opinion holding that that individual right is fundamental and applies to all Americans regardless of where they live. Once again, the decision was 5 to 4.

With Scalia’s tragic passing, there is no longer a majority of support for Heller and McDonald among the justices. Four justices believe law-abiding Americans have the right to own a gun for self-defense, including handguns. Four justices do not. The math is simple — and frightening. So it’s no exaggeration to say that the future of gun ownership hangs in the balance. Justice Ruth Bader Ginsburg, for example, was unequivocal in a speech to the Harvard Club in the District, saying that she looked forward to a day when a future court overturns Heller. The men and women of the National Rifle Association will not sit idly by and watch that happen.

The truth is that President Obama has lost all trust and credibility when it comes to law-abiding gun owners. During his two presidential campaigns, Obama repeatedly paid lip service to gun owners. But during his presidency, he has made his contempt for the Second Amendment unmistakably clear. When Congress refused to pass his gun-control proposals, he said they behaved shamefully and pledged to act without them. In addition, he has called his inability to enact nationwide gun control the biggest frustration of his presidency. Perhaps most revealing of his true intentions, Obama praised the gun confiscation policies of Great Britain and Australia — policies that forced their citizens to surrender lawfully owned firearms to the government for destruction, on pain of imprisonment if they refused.

Obama has already nominated two Supreme Court justices who oppose our fundamental individual right to own firearms safely and responsibly. The NRA knows better than to expect anything different with his third choice. On Wednesday, he nominated Judge Merrick Garland, a member of the U.S. Court of Appeals for the District of Columbia Circuit, to replace Scalia on the Supreme Court. From upholding a federal registry of law-abiding gun owners derived from the instant-background-check system created by the Brady Bill to siding with the District government by voting for a do-over in a Second Amendment decision that invalidated the D.C. handgun ban — exactly what the Supreme Court rightfully struck down in Heller — Garland has proved, the NRA believes, he does not support the Second Amendment.

If Garland joins Ginsburg, Stephen G. Breyer, Sonia Sotomayor and Elena Kagan on the court, we believe they will overturn Heller and McDonald at the first opportunity. While claiming to support Heller during her Senate confirmation hearings, Sotomayor wasted no time in trying to overturn that historic decision. Kagan spent her time in the Clinton White House pushing for gun control. Breyer has made his opposition to Heller and McDonald abundantly clear through his dissents in those cases. And as mentioned previously, Ginsburg publicly spoke about her desire for a future court to overturn Heller.

Make no mistake about it: We believe this would mean the end of the fundamental, individual right of law-abiding Americans to own firearms for self-defense in their homes.

The overwhelming majority of Americans support their right to own a firearm for self-defense. Therefore, the NRA strongly opposes the nomination of Garland to the Supreme Court. Nothing less than the future of our Second Amendment freedom is at stake.