Back in the heyday of the Cold War, Europe had a real problem: even with American military might on its side, the region faced a Soviet military with overwhelming numbers on its eastern flank. If the Soviet Union had opted to invade, there was little NATO could do to stem the flow of Russian armor as it poured through Baltic allies in Estonia, Latvia and Lithuania.

Eventually, NATO’s combined forces could mount a counter-attack, but it would take days or even weeks to amass enough reinforcements. As a result, the use of nuclear weapons to decimate advancing Soviet armor became the strategy of last resort, but many posed concerns that even the use of small, tactical nukes could elevate such a conflict into nuclear war. NATO needed another way.

So the “Assault Breaker” concept was born. In the event of a large-scale invasion, the United States would pair data provided by sensors aboard airborne surveillance aircraft with long-range weapons carried aboard a fleet of America’s massive B-52 bombers. That fleet, composed of 12 aircraft, would each release 20 “Assault Breaker” missiles, each capable of unleashing a “swarm” of 40 smaller sub-munitions that would rely on IR guidance to engage Russian tank columns from above, where their armor is weakest, using forged penetrators.

The idea was simple: a dozen bombers release 240 Assault Breakers from a standoff distance, which then close with encroaching enemy forces and release 9,600 individual explosive penetrators. If only half of these weapons found their marks, it would utterly decimate two-thirds of a Russian tank battalion, rendering the unit all but incapable of continuing its push.

Today, Russia’s stagnant economy is perhaps NATO’s best line of defense, but concerns remain about Russia’s ability to send an overwhelming force into Europe. Despite a sizable NATO presence throughout much of Europe and a push in recent years to bolster defenses, NATO officials acknowledge it would still take days (at least) to mount a sizable response to a Russian invasion of the Baltics, where capturing a thin sliver of territory known as the Suwalki Gap between Poland and Lithuania would sever the Baltic states from allied support. If Russia ever chose to bring the fight to NATO, officials acknowledge, the first days of the invasion would almost certainly go Russia’s way.

So DARPA is dusting off the old approach for what it’s calling “Assault Breaker II.” It, too, would rely on airborne sensors in aircraft like the E-8 JSTARS to provide targeting data to scrambled B-52s, which would rain hell down upon advancing armor columns, decimating an invasion force and buying the allies time to mount an effective counter-offensive. The system wouldn’t win any conflict, but it could slow an invasion down enough to give NATO a chance to respond in force.

The same approach could find use in other contested regions of the world, like the South China Sea. China’s rapidly expanding navy, when combined with its maritime militia and coast guard, could field more than 600 sizable vessels in a Pacific conflict, far more than the United States could amass in the region. Assault Breaker II could be converted for use against ships as well, and although they may not sink larger vessels, they could certainly wreak havoc on operational capabilities.

Most of the technology required to field the Assault Breaker II concept is already on the shelf, according to the Pentagon brass, so they think they’ll be able to have this weapon system deployed to theaters around the world within the decade.