What is the origin of bang for your buck?

Don K. Ferguson writes: When I hear the phrase "more bang for your buck," I cringe because I always thought it had overtones of vulgarity. Was this a respectable phrase that years ago some tarnished by using it in a vulgar sense, or is it, though slang, completely respectable? I heard it used from the pulpit, of all places! The phrase bang for the (or one's) buck may be cringeworthy, but not because of any vulgar origins, but rather because the idea of blowing up the world in an economical manner can bother some people. The phrase, which means 'value for one's money', was originally a political one. Its first use was quite literal: With bang referring to 'firepower' or 'weaponry', it really did mean 'bombs for one's money'. The alliteration of bang and buck helps to make the phrase memorable. The earliest confirmed mention of bang for the buck is found in 1968 in the first edition of William Safire's New Language of Politics. Mr. Safire claims that the phrase was coined in 1954 by Charles E. Wilson, the Secretary of Defense, in reference to the "massive retaliation" policy of John Foster Dulles. While bang has been used in sexual senses since the seventeenth century, it is unrelated to our phrase. However, since people are always eager to give things sexual connotations whether or not they are called for, some prudence would be a good idea.