Former US vice president and businessman Dick Cheney on Tuesday died at the age of 84. He was a key advocate for the invasion of Iraq and a major force behind America’s “war on terror.”Dick Cheney died from complications related to pneumonia and heart and blood vessel disease, his family said in a statement.Cheney served under two US presidents, first as defence secretary during the Persian Gulf War under George H W Bush, and later as vice president under his son, George W Bush, from 2001 to 2009.Read: How 9/11 shaped the ‘Cheney doctrine’For decades, Cheney was a dominant figure in Washington, known for his strong views on national security and his behind-the-scenes influence. In his later years, however, he distanced himself from his own party, sharply criticising current President Donald Trump, whom he once called a “coward” and the greatest threat ever faced by the American republic.Under Bush, he was deeply involved in major decisions, especially those made after the September 11, 2001 terrorist attacks. Cheney supported the government’s use of strong surveillance, detention, and interrogation tactics during that time.