What exactly escalated quickly?

Guardian reporter Glenn Greenwald came to the chivalrous defense of Edward Snowden after Adam Serwer’s father, Daniel, made a comment to Greenwald:

Greenwald’s status as Edward Snowden superfan: Confirmed.

But Daniel Serwer’s son, MSNBC reporter Adam Serwer, took exception to Greenwald:

“Journalist” slap fights are kind of fun, aren’t they?

Editor’s note: Greenwald’s name was misspelled in the original version of this post. We apologize for the error.