It involves making better use of what Ukraine already has in the air," Montgomery said. The United States has already approved the sale of 3,350 of these missiles to Ukraine. These missiles come with one restriction: they can only be used by Soviet-era Ukrainian aircraft, which are unsuitable for this operation. However, if this restriction were lifted, Ukrainian F-16s could be destroying ballistic missile launchers within just a few weeks. A small change in U.S. policy would make a big difference in Ukraine's fight for survival," Montgomery said.