05-26-16: Warren blasts Trump over decades old comments on housing market, stating that he is a "man who cares about no one but himself. A small, insecure money grubber... a man who will never be POTUS." - His response was when he first called her 'Pocahontas'.
https://www.cnn.com/2016/05/25/politics/elizabeth-warren-slams-donald-trump/index.html
11-22-15: NYT, Kovaleskis employer, denounces Trumps claims of Muslims in New Jersey celebrating the 9-11 attacks. Kovaleski states he never said such a thing & NYT claims theres no evidence backing Trumps claims... Kovaleski had actually wrote two articles for WAPO in 2001 & 2003 in confirmation of said topic & cited his source as police departments in New Jersey.
This was just prior to Trumps mocking his speech and mannerisms & that's what he was imitating him talking about.
https://www.powerlineblog.com/archives/2015/11/when-the-press-attacks-donald-trump-the-truth-is-optional.php
07-15-15: McCain gives interview to The New Yorker in which he accuses Trumps rally in Phoenix, AZ as being "very bad... firing up the crazies... the extreme elements within our Republican party. Trump galvanized them and has really got them activated."
Again, prior to and the reason for Trumps 'war hero' comments.
https://www.newyorker.com/news/news-desk/john-mccain-has-a-few-things-to-say-about-donald-trump
07-28-16: Khan, essentially making himself a target in front of a national audience, says in a DNC speech that if it were up to Trump, his son would've never been in America. "He smears the characters of muslims, disrespects other minorities, women, judges, even his own party." He directly spoke to Trump for most of the highly critical speech. It was as if he were chosen to be a speaker, a muslim gold star parent, because he could be considered safe from Trumps return fire. He isn't.
https://abcnews.go.com/Politics/full-text-khizr-khans-speech-2016-democratic-national/story?id=41043609
01-17-17: Waters announces she is boycotting Trumps inauguration, stating "I don't honor him, I don't respect him and I don't want to be involved with him."
The very beginning of their back and forth.
https://www.newsmax.com/Politics/maxine-waters-trump-inauguration-honor/2017/01/17/id/769028/
Every one of these people were the instigators. None of them are above retaliatory critique.