1948, I'd like you to meet 2016:

In this excerpt from Henry Wallace, Harry Truman, and the Cold War by Richard J. Walton ©1976, try (just for fun) replacing "Harry Truman" with "Hillary Clinton," and "Henry Wallace" with "Bernie Sanders":

This was a serious man raising serious questions and this is as good a time as any to deal with them. (J. Raymond) Walsh, and (Henry) Wallace, had to face two age-old political dilemmas: do you fight more effectively from within than from without; is it better to accept the lesser evil or refuse to accept either? As to the first part of the question, many prominent American political figures in recent decades have had to make that choice. All chose to stay, none was effective in changing policy, and they deprived the American people of the healthful public debate that would have resulted had they quit in protest. Dozens of upper-level figures in the Kennedy and Johnson administrations, for example, claimed or let it be understood that they were doing all they could to change policy regarding Vietnam, but none was willing to sacrifice his political future my making a public fight. To put personal future above political conscience is, sad to say, a long American tradition. Unlike these other men, Wallace felt, as Josiah Gitt put it, that he was “honor bound” to force a public debate.

Wallace had tried within the party to cause Truman to modify his “get-tough” policy (with Russia). There was nothing more he could do by remaining within the party than to become an increasingly ignored scold. As to domestic policy, Truman had already begun to move back toward FDR’s policies, whether in response to Wallace or as a pragmatic, bread-and-butter strategy, once cannot be certain, possibly both.

As to the lesser-evil theory, it was a tough question for Wallace sympathizers and was a more difficult philosophical and practical question than the choice between forcing a public debate and keeping quiet. It is an impossible dilemma for a progressive when both parties nominate unacceptable men. If he elects the marginally superior man, he prevents necessary change. If he does not, he gets the worse candidate and still no change. That was the dilemma faced by such progressives as J. Raymond Walsh in 1948. They did not want Truman and they did not want a Republican. But in 1948 party loyalty, with the memory of FDR still fresh, was much stronger among Democrats than it has been in recent years. So these progressives thought wistfully of Wallace, swallowed hard, and supported Truman. There were not unprincipled men and women copping out, but people making the only choice they thought they could make. To them, whose last Republican Presidents were Hoover and Coolidge, it was simply unthinkable to do anything that might result in a Republican victory.