This should be a lesson to everyone in the public eye to not use social media to blow off steam.
The reference was about Army Captain Humayun Khan, an American Muslim who died fighting in Iraq.
Minutes later, after realizing his abject stupidity, Lehrich acknowledged he made a mistake. "I want to apologize for the clearly inappropriate nature and language of this personal tweet. Sorry all."
This "lewd" suggestion was triggered when Trump said Khan "would have been alive today," if he had been president when the officer was killed in Iraq in 2004, because troops wouldn't have been in Iraq. This was said in response to Clinton's remark about Trump criticizing Khan's family this past summer.
Trump went on to declare Khan an American hero.
Then Trump went on to win the debate.