Most of us who are “of a certain age” know that the Republican Party of 2012 is very different than the one we saw in our formative years during the 60’s, 70’s and early 80’s. Although I’ve always had a sense of this — having grown up in Massachusetts where African American Ed Brooks, a Republican, was one of our Senators — but I probably couldn’t name the specifics behind this change. This article in today’s Washington Post, GOP platform through the years shows party’s shift from moderate to conservative, helps fill in those blanks.
The full story is worth reading, but the graphic puts in in visual perspective.
Image and Likeness 
Nor is the Democratic Party the party of JFK and Scoop Jackson. Throughout our country’s history, political parties change. No doubt the Washngton Post would accuse the Republicans of flip-flopping while the Democrats evolve.
You’re quite right David. Polarization and extremism seem to be defining traits of our time. Even in the Church! While Vatican II and the years following did so much for moving forward an Ecumenical perspective in Catholic Christianity, “ecumenism” is a word barely uttered these days. I find it sad.