Source: Wikipedia - Link
Early on a Sunday morning, October 23, 1983, two truck bombs struck buildings in Beirut, Lebanon, housing American and French service members of the Multinational Force in Lebanon (MNF), a military peacekeeping operation during the Lebanese Civil War. The attack killed 307 people: 241 U.S. and 58 French military personnel, six civilians, and two attackers.
There was no reprisal against Reagan for this. Why the campaign against Biden?
Ditto for 9/11 and Bush. They had intelligence that something like that might happen.