"Our goverment and Israel simply CANNOT get away with such a dispicable cover up, murder and war crimes."
If you are right about the Liberty (and that is a very, very big if), it wouldn't be the first, or the last, time that the Government has covered-up or ignored something due to, in their minds, a greater political "good" or need.
Just check out what the US did, or more accurately did not do, regarding Japanese unit 731 activities after WWII and their lack of pursuing war crimes against most of the participants in this activity.
"In the autumn of 1945, MacArthur acceded to granting immunity to members of Unit 731 in exchange for data of research on biological warfare. "The value to the U.S. of Japanese BW data is of such importance to national security as to far outweigh the value accruing from war crimes' prosecution." The BW information obtained from Japanese sources should be retained in 'top secret' intelligence channels and not be employed as war crimes evidence and not be fallen into the Soviet hands. The State Department disagreed over a two year period and the topic simply disappeared."