http://www.hartford-hwp.com/archives/45a/058.html
You have to remember that JFK and MLK were cut down in their prime. Liberalism has advanced incrementally over the past few decades. It drags our nation further to the left each year, with the result that liberals from a few decades ago seem downright conservative in comparison. Ted Kennedy opposed abortion, for example, in 1971, but within a couple of years he was pushing abortion-on-demand, and a few years after that he was calling pro-lifers anti-woman extremists. Al Gore in 1988 wouldn't have endorsed same-sex “marriage” or “civil unions”, yet every Democrat candidate this year has endorsed them. Had Ted Kennedy passed away in 1972, no doubt there would be people here promoting him as a pro-lifer. Had Gore passed away in 1989, we'd have people here holding him up as a model of family values. But they didn't pass away. They lived and today they're openly advocating abortion and homosexuality.
MLK & JFK were as liberal as was politically feasible in their time. No one could have gotten elected or earned any public support by supporting race quotas or open anti-white demagoguery back then. Recall that during the debate over the 1964 Civil Rights Act, Hubert Humphrey famously declared that he would eat the entire congressional record if the bill ever led to quotas or reverse discrimination against whites. By the 1970s, he had changed his tune and was openly advocating quotas as the only way to enforce the Civil Rights Act.
Were MLK & JFK alive today, in their old age they'd be screaming from the rooftops for race quotas, open borders, the homosexual agenda, wholesale abortion-on-demand, and a dozen other things they would never have dared to support circa 1963 or 1968.
You make a good case - - up to a point. With politicians, you might be right - they are known for a mentality that puts finger to the wind to see which way it's blowing.
But politicians are "men of action" not men of thought - and following the way the wind blows - in many strange ways and wonderful ways - works for politics and democracies.
But MLK was a man of thought - he wasn't a politician. In '64 much of the civil rights community was moving past him. SNCC, CORE, the Panthers, etc were "moving on to the next level". Even Jesse Jackson was seen as an embarrassment back then - Uncle Tomish to say the least. Of course those young angry and impatient young people could never have given birth to the modern civil rights movement. That took a man with the mind like the one MLK had...
I heard MLK give a speech in 1964 - he had given his "I have a Dream" speech in Washington, and later came to Chicago and gave what I thought at the time was the same speech. It wasn't.
What he had done was take the part of the speech everyone was quoting and talking about from the Washington speech and made the whole speech about what his dream was. It was eloquent. It was beautiful. At some point I realized I was crying - and looked around and noticed hundreds of other people were also crying.
And so, I believe you are wrong. MLK didn't even change with the movement as it was unfolding at the time... Maybe someday someone will find notes on the Chicago speech and you'll see what I'm talking about.