GOP congressman tries to mansplain border security to a security expert -- and it hilariously backfires
Dan Crenshaw speaking with attendees at the 2018 Student Action Summit hosted by Turning Point USA at the Palm Beach County Convention Center in West Palm Beach, Florida. (Gage Skidmore/Flickr)

Freshman U.S. Rep. Dan Crenshaw (R-TX) has been on the job for less than a month and already he's in hot water.

Crenshaw posted a remarkably condescending tweet mansplaining to a lifelong national security expert, who happens to be a woman, suggesting he could help teach her a thing or two about border security.

Juliette Kayyem is a John F. Kennedy School of Government Harvard professor, a national security analyst for CNN, and serves on the Council on Foreign Relations. She has served on Secretary Jeh Johnson’s Homeland Security Advisory Council, and if that weren't enough, she was the U.S. Assistant Secretary of Homeland Security for Intergovernmental Affairs.

In the 1990's she worked at the Dept. of Justice and served as an advisor to Attorney General Janet Reno. She was appointed to the the National Commission on Terrorism, and was Massachusetts’ first Undersecretary for Homeland Security.

Kayyem has also written a book on homeland security for homeowners and was a columnist writing about national security for the Boston Globe.

Rep. Crenshaw was a Navy Seal.

On Thursday Kayyem responded to a CNN reporter announcing the Border Patrol had "made the largest seizure of fentanyl in the agency's history," by reminding Twitter users that the seizure of the fentanyl was made "at the PORT OF ENTRY," which she repeated several times, suggesting a wall would do nothing to stop the illegal drug from entering the U.S.

Congressman Crenshaw apparently saw an opportunity to condescendingly school the former Homeland Security Assistant Secretary, while bragging that he was "in a vehicle with CBP at the border."

His mansplaining did not sit well with many on the social media platform.

Take a look: