Cold Case JFK, airing tonight on PBS at 9 pm, re-explores the JFK assassination with expert testimony and fresh technology. The big takeaway is that firearms experts Lucien and Michael Haag have concluded that the magic bullet — the one that caused seven two wounds in President John Kennedy and five in Governor John Connally, and yet was found on a stretcher in pristine shape — is not a joke. The most ridiculed shooting scenario in the history of modern forensics is scientifically supportable, they’re saying. Bad news for the conspiracy gang, of course, but they’re used to that by now.