Trump articulates in his bombastic way the policies and animus that the GOP has promoted in the last 20 years. There are no Rockefeller Republicans. No person like Senator Dirksen or even Bob Dole or Jack Kemp could survive a primary in the modern Republican party.

This thread was inspired by an opinion piece which included:

Trump is a byproduct of all the toxic elements Republicans have thrown into their brew over the last decade or so — from birtherism to race-based hatred of immigrants, from nihilists who shut down government to elected officials who shout “You lie!” at their commander in chief.
It was fine when all this crossing-of-the-line was directed at President Obama or other Democrats. But now that the ugliness is intramural, Trump has forced party leaders to decry something they have not only tolerated, but encouraged.
...
“All of our veterans, particularly P.O.W.s, deserve our respect and admiration,” said Jeb Bush. The Republican National Committee was quick to lay down a similar principle, saying, “There is no place in our country for comments that disparage those who have served honorably.”
No place except a presidential campaign, that being the 2004 attempt to destroy the honorable Vietnam service of candidate John Kerry. Where was Bush’s “respect and admiration” when his brother was benefiting from a multimillion-dollar smear of a Navy veteran with a Bronze Star and a Purple Heart?
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It that analysis correct? I think it is and explains why Trump is leading in the polls including now ones that included his attack on McCain.