Thanks to recent developments in North Korea’s long range ballistic missile programs, a great deal of attention has been paid to America’s missile defense infrastructure.  From the Aegis Missile Defense System powered by America’s Naval presence in the region, to THAAD launchers in both South Korea and Kodiak, Alaska, all the way to America’s sometimes questionable mainland Ground-based Midcourse Defense system, the United States, and its media, have devoted a great deal of attention to ensuring these platforms not only function, but serve as a form of deterrent.  The message the U.S. sends with each successful missile intercept is simple: if you attempt to fire an ICBM at the United States, it won’t ever reach its target.

That, in and of itself, may well serve as a formidable deterrent to Kim Jong-un, who has issued repeated threats of pre-emptive nuclear strikes on American and allied targets, but our ability to neuter Kim’s nuclear pursuits are only a half of a larger deterrent strategy.  The other half harkens back to the days of mutually assured destruction: America’s own nuclear arsenal.

It stands to reason that if North Korea ever were to somehow successfully execute a nuclear strike on U.S. soil, the United States would respond in kind with its far superior stockpile of nuclear weapons.  As a frame of reference, North Korea is believed to possess as many as 10 to 20 nuclear weapons, each similar in yield to the atomic bombs the United States dropped in Hiroshima and Nagasaki at the conclusion of WWII.  As of 2015, the United States arsenal included 4,571 nuclear warheads, many that are more powerful than Kim’s by a factor of exponents.  An all-out launch from each side would see some portions of the U.S. destroyed, and every structure in North Korea entirely wiped out multiple times over – not that any such event would ever occur.

Still, the deterrent offered by America’s ability to launch a massive and devastating retaliatory strike was seen as enough to keep the mighty Soviet threat at bay throughout the Cold War, and it stands to reason that Kim Jong-un understands that a nuclear launch against the United States would likely not just end in his removal from power, but with his nation itself practically being removed from the map.

There is no substitute for the prospect of a devastating nuclear response to deter that threat,” Air Force Gen. Paul J. Selva, vice chairman of the Joint Chiefs of Staff, said at the Air Force Association’s Mitchell Institute on Thursday.

“We played these games as kids, but the logic is the same,” he said. “If you attack me, I have the capacity to return that attack, and I will return it with a degree of violence that is commensurate with the violence you’ve done to me. If you can accept that, then we reach a state of equilibrium. It is will, capacity and capability. If you don’t have all of those, deterrence fails.”

There is, however, a problem with relying on America’s nuclear weapon stockpile as a means by which to deter aggressive nuclear states: our missile platforms are under maintained and extremely outdated.  America’s nuclear triad, which is the term used to describe the three methods of nuclear weapon delivery employed by the United States, offers a great deal of redundant protection, but each leg of the triad is also extremely dated.

The first leg, America’s Ohio class nuclear submarines, were first built in 1976, more than forty years ago.  Our Minuteman III ICBMs were first fielded in the 1970s as well, and the third leg, comprised of B-52 bombers delivering the weapon systems, are based on platforms that first took to the sky in the 1950s.  While each of these systems have received updates over the years, those updates have not come with the frequency required to keep them on pace with the latest offerings from potential competitors like Russia, who announced a new ICBM design as recently as last year.