EXETER, N.H. — Tucked inside a New Hampshire office park, a small refinery zaps mining waste with electricity to tease out critical minerals needed for key U.S. weapons systems, including missiles used in the Iran war. It’s just the latest critical minerals company the government has backed. While the White House is demanding military contractors speed up production, it’s also imposing stricter rules banning them from sourcing critical minerals from China. The metals that Phoenix Tailings refines and other critical minerals play “an outsized role” in defense systems, Balladon said. A $150 million weapons system won’t work if it’s missing critical minerals that may be worth only $20,000 to $30,000, he said.