why is it "critical" to USA?"antimony may seem like an obscure...

why is it "critical" to USA?

"antimony may seem like an obscure material, but it is vital in the defense industry, with critical uses in nuclear weapons, infrared missiles, and night-vision equipment. No country maintains as dominant a grip on the metal’s global trade as China, which accounts for nearly half of all production and more than 60 percent of U.S. imports. Beginning Sept. 15, Beijing will require exporters to apply for a license for certain antimony products as well as require permission for related smelting and separation technology exports."

is nuclear weapons classified as "defense"? comparing US and AU which County is more likely to be attacked and that "defense" is more critical to them?
if/when US change their policy on semiconductor chips to China or end other restriction, China may change the policy on Antimony, imo.