Goldwater was defeated only because Johnson and his crew successfully painted him as a warmonger. Nobody will be able to get away with that with Ted Cruz.
A woman was quoted as saying, "I was told that if I voted for Barry Goldwater, we'd be at war in six months. I did--and we were."
There was a second reason: The RNC and the Rockefeller wing of the party sat on their hands (and wallets). Goldwater got no help, save from his own voters (like me).
There is a definite risk that the GOPe and the RINO wing will do the same thing to Cruz -- leaving it up to his voters (like me) again.
Lyndon Johnson ran as a peace candidate in 1964, saying, "I won't send American boys to do the fighting for Asian troops," and we all know how that turned out.
Not only that, Johnson won because he was the one in the public’s eye that was the force of stability and healing coming off the heels of JFK’s assassination.
There was no way Republicans could have won the presidential race that year.