Bolton's Resignation Letter: Short, Simple

Former National Security Adviser John Bolton's resignation letter Tuesday to President Donald Trump was short and simple.

"Dear Mr. President," the letter began after the address, "I hereby resign, effectively immediately, as assistant to the president for national security affairs.

"Thank you for having afforded me this opportunity to serve our country," the letter concluded.

Bolton's letter was posted on Twitter by CBS News White House correspondent Mark Knoller.

President Trump tweeted Tuesday that he had fired Bolton, 70, from his rocky 17-month tenure, after repeated clashes over various global security issues.

Bolton, however, tweeted that he offered to resign Monday night and that "President Trump said, 'Let's talk about it tomorrow.'"

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