Jofi Joseph, 40, was fired from his job on the National Security Council.
Joseph posted under the now defunct Twitter name @NatSecWonk.
"Was Huma Abedin wearing beer goggles the night she met Anthony Weiner," he tweeted, referring to the scandal-hit former New York mayoral candidate and his wife, a former aide of Hillary Clinton.
Joseph joined Republican attacks on Mrs Clinton for perceived failings of her handling of last year's attack on the US diplomatic post in Benghazi, Libya.
He tweeted that Mrs Clinton "had few policy goals and no wins" in the Middle East.
He said Chelsea Clinton was "assuming all of her parents' vices".
White House officials had worked over months to discover the identity of Joseph. His travel and shopping habits had been profiled by parsing over 2,000 tweets.
His tweets had been "obsessively and angrily followed" by Washington officials.
Now we know what Obamas IT geniuses have been focused on...
http://www.bbc.co.uk/news/world-us-canada-24637160