(Reuters) – Family members of those who died in the attacks on Sept. 11, 2001 in the United States, launched a fresh campaign on Tuesday against LIV Golf, with the Saudi-backed circuit to hold a tournament at Trump National Doral Golf Club beginning Friday. The advocacy group 9/11 Justice criticised the circuit in a television advertisement in Florida ahead of the Miami tournament and will host a news conference on Thursday, while urging former U.S. President Donald Trump to cut ties with LIV. Fifteen of the 19 hijackers on Sept. 11 were from Saudi Arabia. The kingdom has long denied a role in…