The Senate voted Wednesday 97-1 and the House 348-77 to override President Barack Obama’s veto of legislation that would allow the families of 9/11 victims to sue Saudi Arabia for its alleged role in the Sept. 11, 2001, terrorist attacks. But that is only the beginning of what will be an exceedingly complicated legal strategy to prove that the Arab country, from which 15 of the 19 9/11 hijackers came, bears responsibility for what took place.
