You can't run anything, much less the United States is a national security policy without having people who are willing to put uncomfortable truths in front of the president,” the Connecticut Democrat said.

National security adviser Mike Waltz is leaving his White House post, although soon after reports about his departure were published, President Trump announced he plans to nominate him to be ambassador to the United Nations.

President Donald Trump has gone through his share of national security advisers. But he doesn't hold the record, yet.