Suppose a Mach 2.5 (850 m/s) missile aiming at you. You blind it 4km out (about the same distance as Phalanx can engage) (suppose its sea-skimming so coming rig

Suppose a Mach 2.5 (850 m/s) missile aiming at you. You blind it 4km out (about the same distance as Phalanx can engage) (suppose its sea-skimming so coming right onto your side). It takes 4.7 seconds to impact you. A DDG-51 is 150 meters long. If it was aiming center of mass, you need to induce a 75 m change in relative position in 4.7 seconds to cause a miss. This can be accomplished by like 6.8m/s^2 acceleration. Ok, so thats like 0.7G, super won't work. But say its subsonic (mach 0.9... so like 300 m/s). Now your talking like 13.3 seconds to impact, and now need like 0.85 m/s^2 acceleration to induce a clean miss. Ok cool, that has some utility. Oh, and totally, its a stop gap. But it's still useful to learn things like... how do gimballed laser systems behave on a ship? What type of maintenance is required? What unexpected interference is induced?