WASHINGTON (AP) — Five former secretaries of defense are calling on Congress to hold immediate hearings on President Donald Trump’s recent firings of the chairman of the Joint Chiefs of Staff and several other senior military leaders, according to a letter obtained by The Associated Press. The five men — who represented Republican and Democratic administrations over the past three decades — said the dismissals were alarming, raised “troubling questions about the administration’s desire to politicize the military” and removed legal constraints on the president’s power. Late last week, Trump fired Air Force Gen. CQ Brown Jr. as chairman of...