[1] He is a former Director for Asian Affairs at the White House National Security Council (NSC) during the George W. Bush administration, with responsibility for Japan, North and South Korea, Australia, and New Zealand.

[9] He held the D. S. Song-Korea Foundation Chair in Asian Studies and Government in the Walsh School of Foreign Service and directed the American Alliances in Asia Project at Georgetown University until 2004.

[14] Cha had reportedly in December 2017 privately expressed disagreement with the Trump administration's consideration to launch a limited strike at North Korea and to withdraw from the United States–Korea Free Trade Agreement.

"[16] In 2020, Cha, along with over 130 other former Republican national security officials, signed a statement asserting that Trump was unfit to serve another term.

Cha wrote this in response to previous research on the subject, which he felt focused too heavily on their respective historical antagonism.

[19] In 2005, Cha co-authored Nuclear North Korea: A Debate on Engagement Strategies with Professor David Kang of Dartmouth College and its Tuck School of Business.

[21] Cha published a book on East Asian security in 2016, Powerplay: The Origins of the American Alliance System in Asia.