The CIWS Phalanx was designed to defeat better anti-ship missles than the Exocet. Heck, the Wisconsin took out a exocet class target with a Twin 5"38 gun using 1930 technology.
Send them exocets and we will fill the Straights with depleated uraniun.
Are you talking about the Gatling guns on the destroyers? Apparently the GG was designed to literally create a 'curtain of lead' to make an incoming missile or rocket self-destruct. I think I recall 6K rounds/minute of depleted-uranium rounds...