The JFK assassination tells us differently, unless you believe Oswald did it on his own.
Read Bugliosi’s latest book. Or read Posners book. Also, check out the reearch done on the bullet trajectory and how one pristine bullet behaved 100 percent the same when fired at two cadaver dummies arranged like Kennedy and Connolly. Yes, Oswald did act alone, and that is becoming more and more the accepted view since every single conspiracy theory has been debunked with facts.