FORT CARSON, CO - APRIL 28: Members of the 2nd Stryker Brigade Combat Team fire a Javelin missile from a Stryker Infantry Carrier Vehicle during a live-fire training exercise on April 28, 2022 in Fort Carson, Colorado. The Javelin anti-tank missile system uses automatic infrared guidance to track targets and has the ability to use top attack to hit targets from above where armor is thinnest. The U.S. military has sent almost a third of its javelin missile supply to Ukraine which plays a vital role in it's fight against Russia. (Photo by Michael Ciaglo/Getty Images)

WASHINGTON (AP) — When President Joe Biden visits a Lockheed Martin plant on Tuesday that manufactures an antitank weapons system, he’s certain to herald the U.S.-made arms as a gamechanger in Ukraine’s stiff resistance to the Russian invasion. But Biden’s coming visit to the Alabama factory line that makes the Javelin weapons system is also drawing attention to a growing concern as the war drags on: Can the U.S. sustain the cadence of shipping vast amounts of arms to Ukraine while maintaining the healthy stockpile it may need should conflict erupt with North Korea, Iran or elsewhere?