Our attention is focused on the terrorist attack in Boston last week, but just two weeks ago we were gripped by North Korean threats of a new Korean War and the possibility of New York’s being hit attacked by long-range missiles. While North Korean promises of thermonuclear war have faded from the news for the moment, the threat hasn’t gone away for good.

The national-security challenges our country faces from the advances in ballistic-missile and nuclear-weapon programs continue apace. Global missile- and nuclear-proliferation problems are real, and they can’t be ignored. So the development and deployment of missile-defense programs must be a priority for American security.

Take North Korea. Bluster, belligerence, brinkmanship, and blackmail are routinely directed at Washington. Yet Pyongyang’s actual ability to carry out threats against us is improving – and significantly.

In December, North Korea launched a long-range, multi-stage ballistic missile that put a small satellite into orbit. The real concern wasn’t the satellite itself, but Pyongyang’s ability to put a satellite into space at all. If you can put a satellite of as little as 1,000 pounds into orbit, you can launch a nuclear warhead toward a target anywhere on the Earth’s surface.

Then, in February, North Korea conducted its third nuclear test since 2006, which may have used a smaller test apparatus of the sort that would be needed for the development of an intercontinental ballistic missile (ICBM) warhead.

There is plenty of debate within the U.S. intelligence community as to whether North Korea already has a functional nuclear warhead that it can mate with the missiles of various ranges currently in its arsenal. But there is little doubt that we will be near, or at, the top of the targeting list when they do have one.
Then there’s Iran. Although they are also out of the news at the moment, Iranian centrifuges continue to spin, producing kilograms of low- and medium-enriched uranium, which — if further enriched — could be used in nuclear weapons.

The ever-cautious International Atomic Energy Agency (IAEA), the United Nations’ nuclear watchdog, suggests that Iran may be involved in the development of a nuclear weapon for that fissile material.

While publicly available intelligence estimates differ, Tehran may have the wherewithal to produce its first nuclear weapon in the very near future.

Iran’s ballistic-missile program isn’t any more comforting.  In 2009, Tehran was able to put a satellite into space using its own launch vehicle. Today, the U.S. government estimates that Iran will have an ICBM by 2015, adding to what is already the largest ballistic-missile arsenal in the Middle East.

While seemingly obvious, it’s worth pointing out that the principles of physics that would allow North Korea to put a warhead anywhere on the Earth’s surface also apply to Iran.

Another inconvenient fact is that both the North Korean and the Iranian nuclear and missile programs could move along faster than currently assessed if either receives outside assistance — including from each other, which some analysts strongly believe is ongoing.

We shouldn’t overlook the Chinese or the Russians, who are also modernizing their strategic arsenals.

Beijing has moved its nuclear arsenal from silo-based to road-mobile systems and is sending its nuclear forces to sea aboard submarines. Moscow still relies heavily on its strategic forces and is developing, or deploying, new sea- and land-based ICBMs.

The obvious question is: What should we do?

As we all know, diplomacy and punitive economic sanctions haven’t stopped North Korean or Iranian missile or nuclear programs — despite years of trying. Military responses are filled with risks, and Cold War–era “Duck and Cover!” isn’t a good alternative, either.

Nothing makes more sense than investing in American missile defenses.

With advances in missile defense, a robust, layered, capable system will not only protect us from enemy ballistic missiles and their nuclear and other payloads (e.g., chemical, biological, conventional, or electromagnetic pulse), but it will provide decision-makers with additional policy options beyond massive retaliation.

In addition, due to missile defense’s ability to blunt the effectiveness of the ballistic-missile threat, it may well deter aggression with these weapons against us in the first place.

The best option now is to move forward vigorously with funding, developing, and deploying American missile-defense systems to protect the homeland, to protect our troops overseas, and to protect our allies and friends from the growing nuclear and missile menaces around the world.

— Peter Brookes is a Heritage Foundation senior fellow and a former deputy assistant secretary of defense. Twitter: @Brookes_Peter