DUBAI, United Arab Emirates (AP) — After Congress passed a new law allowing Sept. 11 victims’ families to sue Saudi Arabia in U.S. courts, opponents mounted an expensive political campaign, including paying American military veterans to visit Capitol Hill and warn lawmakers about what they said could be unintended consequences. What few people knew, including some of the recruited veterans themselves, was that Saudi Arabia’s government was largely paying for the effort, worth hundreds of thousands of dollars. Despite a World War II-era U.S. law requiring lobbyists to immediately reveal payments from foreign governments or political parties, some of the campaign’s organizers failed to notify the Justice Department about the Saudi kingdom’s role until months afterward, with no legal consequences. Even now, some opponents of the law, the Justice Against Sponsors of Terrorism Act, still won’t say to whom or how many exactly they paid thousands of dollars each to influence state a...