Photo: National Nuclear Security Administration

The U.S. has been “modernizing” its 20th century nuclear arsenal for about a decade.

But while the stated goal has been to increase safety, and extend the life of the existing Cold War thermonuclear stockpile, there has been a targeting improvement which has wrought a “revolutionary impact” on WMD strategy in the 21st century, according to The Bulletin of the Atomic Scientists.

The “super fuze” that’s now incorporated on U.S. submarines worldwide has essentially tripled the “killing power” of the U.S., achieving insurmountable superiority against other nuclear powers, including Russia, the former Cold War adversary.

“This vast increase in U.S. nuclear target capability, which has largely been concealed from the general public, has serious implication for strategic stability and perceptions of U.S. nuclear strategy and intentions,” writes Hans Kristensen, director of the Nuclear Information Project with the Federation of American Scientists, in the assessment of the new arsenal.

The new mechanism was developed in the 1990s, and since 2009 has been incorporated on all of the U.S. Navy’s W76-1/Mk4A warheads.

Essentially, the new fuze allows greater accuracy over “hard targets,” such as Russian ICBM silos. The fuze does this since it does not have fixed height-of-burst parameters – and instead adapts upon re-entry to almost ensure its greatest lethal payload is focused on the target below.

Instead of needing three standard submarine-based missiles, then, destruction of a priority target would only take a single missile, writes Kristensen.

The W76 is the most numerous warhead in the U.S. stockpile, and would now have capabilities of destroying virtually any target in the world, he adds. By increasing that “efficiency,” more missiles and warheads are freed up to target cities and other “soft” targets across the world, according to the analysis.

The missile now allows the U.S. to ostensibly be in the position of being able to “win” a first-strike nuclear offensive, according to the assessment.

The American navy’s fleet of submarines in the North Atlantic and elsewhere would allow a successful strike to wipe out Russian nukes, with just a 15-minute warning, due to antiquated ground-based radar warning systems. (The U.S. has a space-based infrared early warning system which gives American leaders approximately 30 minutes of time to decide to push the button). The Russian warheads would thus be destroyed before a counterattack could be initiated, he adds.

The U.S. superiority is not necessarily good news for nuclear strategic stability, Kristensen writes. Russia is already in the process of testing a nuclear-powered underwater unmanned vehicle to threaten U.S. ports and coastal areas. The missile gap is not lost on Vladimir Putin, the Russian leader, either. He addressed an uncertain future in ominous tones last summer at a forum in St. Petersburg, saying that the U.S. stance on missiles that was ostensibly directed at Iranian distance capabilities was instead proving to threaten Russia.

“I don’t know how all this is going to end,” Putin reportedly said. “What I do know is that we will need to defend ourselves.”