Al Root

President Donald Trump wants the Department of Defense to start testing nuclear weapons again, something America hasn't done since 1992.

It's a decision that could have geopolitical ramifications. For now, investors want to know what it could mean for defense stocks.

The short answer is not much -- though they might want to brush up on America's nuclear capabilities.

For starters, America and Russia have the largest nuclear stockpiles with an estimated 5,400 and 5,300 warheads, respectively, according to the International Campaign to Abolish Nuclear Weapons. China is number three at 600 warheads, and six more countries have nuclear weapons.

In the U.S., government agencies design and build nuclear warheads. Some private companies, including BWX Technologies and Honeywell, maintain stockpiles and government-controlled sites. And assets supplied by the private sector, such as submarines, missiles, and bombers, can deliver nuclear weapons.

Those assets form the Pentagon's " nuclear triad," which refers to America's ability to launch nuclear strikes from land, sea, and air.

On land, Boeing built the Minuteman Intercontinental Ballistic Missile system, which is being replaced by Northrop Grumman's Sentinel program. The two companies also make bombers capable of delivering nuclear weapons from the air. General Dynamics makes Ohio-class submarines capable of launching nuclear weapons.

None of the stocks were reacting much to the nuclear testing news. General Dynamics shares were down 0.9% in midday trading, while the S&P 500 was down 0.4% and the Dow Jones Industrial Average was up 0.3%.

Boeing shares were down 4.4%, but that came after Deutsche Bank analyst Scott Deuschle downgraded shares to Hold from Buy after Boeing reported third-quarter numbers on Wednesday.

Northrop shares were flat. BWX Technologies' stock was up 0.8%.

Honeywell stock might look like it was down 5% depending on where investors look. But it spun off Solstice Advanced Materials stock today. Adjusted for the spin, shares were up 0.4%.

More broadly, nuclear testing highlights growing global tensions around the world, which has the U.S. and Europe spending more on national defense. That has been a boon to defense stocks.

Coming into Thursday trading, the iShares U.S. Aerospace & Defense ETF was up almost 50% year to date.

Write to Al Root at allen.root@dowjones.com

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October 30, 2025 14:52 ET (18:52 GMT)

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