Editor’s Note: Coauthored by James Jay Carafano.

Wednesday marks the 33rd anniversary of Ronald Reagan’s historic “Star Wars” speech, in which he introduced the Strategic Defense Initiative (SDI) to the American people. The intent was to protect the U.S. from nuclear attack.

Today, when a ballistic missile fired from anywhere in the world can reach the United States within 33 minutes, Reagan’s bold vision for a multi-layered missile defense system is more necessary than ever.

SDI was intended to counter the Soviet nuclear threat. Unified ground- and space-based platforms would detect and destroy ballistic missiles after launch. It was a forceful rejection of the doctrine of Mutually Assured Destruction (MAD), a strategy which relied on the specter of mass casualties on both sides to deter nuclear war.

Reagan’s victory-based approach was mocked by the political Left, which favored MAD rather than trying to beat the Soviet Union in the arms race. But that’s exactly what Reagan did; six years later, the Berlin wall came down.

Unfortunately, cavalier attitudes toward missile defense remained among much of the political class. They had first dismissed SDI as “Star Wars” sci-fi — until the technology actually existed. Then, they condemned it as too provocative — until the USSR collapsed.

Finally, came the excuse that America no longer had a major global adversary to justify the exercise.

The last surviving piece of Reagan’s SDI vision, Brilliant Pebbles, was a satellite-based platform which would have relied on kinetic projectiles to intercept missiles in low orbit. President Bill Clinton killed the program via budget cuts, even though subsequent experiments by NASA and leaps in technology made such a system eminently feasible.

Indeed, technologies developed under SDI contributed to ballistic missile capabilities the United States has today. Moreover, SDI research produced innumerable benefits beyond missile defense: cheaper and more capable computer chips, optics equipment, and specialized materials that businesses and consumers now take for granted.

But despite the progress made, SDI was never fully realized. The United States still lacks a unified missile defense plan, while the world remains a very dangerous place.

Although the Soviet bloc has been relegated to the ash heap of history, we face a new litany of global threats. Ballistic missiles are becoming more accessible to countries like North Korea and Iran. North Korea has repeatedly threatened the United States and its allies — South Korea and Japan — with attacks using its nuclear- ipped ballistic missiles. Iran continues to improve the range and sophistication of its missiles, while Russia aggressively modernizes its nuclear weapon arsenal and threatens U.S. NATO allies.

Our conflicts with these nations have thankfully not escalated to shooting wars. Yet. But that makes it all the more important to develop a new SDI for the 21st century while we still have the time.

Even if it remains in its silo or submarine, a missile targeted at an American or allied city with a madman at the controls could effectively hold U.S. foreign policy hostage.

The unconventional aspect of America’s current enemies — some driven by ideologies yet more reckless and bloodthirsty than Communism — means that mere deterrence and guarantee of reprisal will be insufficient to protect our people. Americans should be able to live secure in the knowledge that we can shoot down any weapon launched at them by another country or faction.

They will only do so when the political will exists to build a comprehensive missile defense. Many lawmakers are simply ignorant of America’s current vulnerability to attack. Some conflate missile defense with their understandable wariness of military adventurism. Others, like our current Commander in Chief, seem motivated by a desire to reduce America’s leadership role in the world generally.

Reagan realized that weapons of mass destruction, like evil men, would never be completely eliminated from the world stage. The greatest insurance against nuclear arms and their proliferation is technology which renders them useless — a far better guarantor of world peace than fragile treaties with rogue nations. As he told Soviet Secretary General Mikhail Gorbachev, “The genie is already out of the bottle. Offensive weapons can be built again. Therefore I propose creating protection for the world for future generations, when you and I will no longer be here.”

For the sake of those future generations, our leaders should take a page from Reagan and embrace a strong missile defense.

Republished from The Heritage Foundation.