This raises a tricky question: Should the United States open or reopen a production line for nuclear weapons in order to avoid losing their manufacturing know-how, the way we do with M1A2 Abrams tanks? The United States once produced thousands of tanks per year. Today, there is only one tank plant left open in the nation, the Lima Army Tank Plant. For years, US Army leaders have asked Congress to stop purchasing new tanks because they didn't need them, but Congress kept ordering the Department of Defense to buy tanks anyway. They did this for two reasons. First, because the tank plant is a source of jobs in Ohio. Second, because tanks, especially modern, 21st century tanks, are specialized tools, and we wouldn't want to forget how to build them. An argument is made than it is cheaper to keep producing tanks that are not needed than it would be to restart a tank production line if one didn't exist. The argument is sensible and most likely true. After the US Air Force ordered an early end to the production of the F-22 Raptor in the early 2010s, the production line was dismantled. A report in the last few years estimated the cost to restart the production line in the billions, if not the low tens of billions.

So, back to nuclear weapons. The United States manufactured tens of thousands of nuclear weapons during the Cold War. Most of these weapons have been decommissioned and the production lines have been shut down. The United States no longer manufactures nuclear weapons. Now, the incoming Ground Based Strategic Deterrent will be built by Northrop Grumman in the next few years to start replacing the aging Minuteman III ICBMs, but the warheads and the nuclear cores will be recycled from existing ICBMs.

Which raises a question: How would the United States replenish its nuclear weapons if the need arose? For example, after a nuclear war, where the US lost or expended 80% of its arsenal? The question of what to do after a nuclear war may sound absurd to some, but it's a worthwhile and interesting one. More on point, what if the nuclear cores degrade to a point where they may no longer work? This is essentially what the Department of Energy's Nuclear Stewardship Program is for. It's a program that costs billions of dollars a year and uses supercomputers to model the slow degradation of the nuclear cores in the stockpile.

But here's where it gets trickier. The New START treaty will expire in 2026. If it is not extended or replaced by a new treaty, there will be nothing stopping Russia from expanding its nuclear arsenal. China is also expanding its nuclear arsenal as we speak. Last week's report by the Department of Defense claims that China will have 1,500 nuclear weapons within a decade or so. China is building new nuclear weapons. The United States is not. And China is not bound by any arms control treaty.

Now, the US also happens to have about 1,400-1,500 nuclear weapons deployed, plus a few thousand more in storage, disassembled.

But what if China decides at some point to push past 1,500? To 2,000? 5,000?

A country with 5,000 nuclear weapons could conduct a first strike against a country with 1,500 nuclear weapons, on a 2:1 ratio, and still have 2,000 nukes in reserve for further strikes. This is why the nuclear arms race happened between the US and the Soviet Union in the first place. Any disparity in the deployed arsenals gives the side with more the advantage. So if China ever decides to expand beyond 1,500, the strategically sound move for the US would be to start building more, to match the Chinese production. It would be tragic, but it's not impossible.

But the US no longer manufactures nukes, so the old production lines would need to be reopened.