Why has Mike Waltz been dropped as US National Security Advisor?

The decision marks a significant first major personnel change in Donald Trump’s second term as national security adviser. Mike Waltz was removed from his role despite weeks of speculation about his abrupt exit following his inclusion in a chat group of senior officials sharing classified information. While the immediate cause for his departure remains unclear, it signals ongoing efforts to realign key Trump administration teams amid growing political and personal tensions within the White House.