As a forward, I apologize profusely if I do anything incorrectly. I do not mean to distress; please forgive whatever errors I may make in creating this. Although I have been watching little_details for quite some time, I have never actually posted anything here. So, disregard if I am bothering. Nothing like this came up in my searches.
If this sounds immensely stupid, ignore. Please.
Setting: The United States of America, 1960s
Research: Google, Wikipedia, The LBJ Library, The Alternate History forum, The Kennedy Assassination: 24 Hours After, JFK Reloaded (a tasteless physics simulator), and Death of a President
So here is the scenario (this is going to be a tad long): The date is November 22, 1963 and the stage is set in Dallas, Texas. Everything seems to be going as planned. The people are cheering, the President is smiling and Lee Harvey Oswald is preparing to make his famous shot.
As the motorcade turns onto Houston Road, the gathered crowds erupts in applause. This startles the would-be assassin so much that has he has a fit of panic and accidentally shoots as the President's car is passing the Criminal Courts Building. The gunshot is loud, but the terrible noise is drowned out by the happy people. Those few who do hear it, like the Kennedys themselves, suffer a moment of confusion before dismissing it. Only the doomed Mr. Connally recognizes the danger. He quietly mutters "Oh no, oh no." and tries to turn to look at the President behind him. Another shot rings out,, but misses and lodges itself in the street.
Oswald's composure is now in ruins. He fears that he will soon lose his target. Surely, they will be searching for him now. His heart thumps in his ears as the third shot is fired. Contrary to popular belief however, trembling hands do not help a good marksman. The Presidential car is now heading past the County Records Building.
The shot hits on the interior, toward the top of the front passenger side door. The Magic Bullet ricochets and travels through Roy Kellerman's neck (front passenger) and lodges itself in Bill Greer's (driver) brain thus incapacitating both drivers. Bill slumps over onto the steering wheel and the car begins to accelerate at an alarming rate. The Secret Service agents in the car behind seem utterly helpless.
There is something terribly wrong here, the crowd realizes. A few try to flee the scene but most seem rooted to the spot in silent horror. The car swerves toward the fountain. To think the day began so beautifully... While the President and his wife are frozen in shock, Connally climbs over his seat and desperately attempts to steer the car away. He manages to avoid slamming into the fountain, but injures several civilians in the process.
His heroics are for naught, his steering manages to prevent a collision with the Secret Service car but results in the Presidential car slamming into the VP's automobile. Kennedy's neck snaps upon impact and Connally is rewarded for his efforts by being flung bodily from the vehicle. Jackie suffers a ruptured aorta and dies at the scene. Nellie miraculously manages to leave the scene with nothing more than a few bruises. The car comes to a stop.
In the VP car, Vice-President Lady Bird is hospitalized for mild injuries. LBJ suffers a stroke while being transported and is put into a coma. Hurchel Jacks (driver of VP car) later dies in the emergency room.
Oswald is later killed while attempting to flee the scene.
Sorry for being so lengthy. I realize that the probability is rather... unlikely. I did use a simulator to make the shot go off. It is possible, albeit highly unlikely.
1.) My research tells me that Speaker of the House, Democrat John McCormack would become president. However, I am having difficulties finding how a McCormack presidency would look. How would the political landscape look, How do civil rights go, etc.?
2.) What happens in the event of the Vice President entering a coma? As far as I am aware, there were no laws in place regarding such a scenario until 1967. If my memory serves me right, JFK tried to introduce such a bill during his presidency but it was shot down.
3.) How does the general public react to the Executive branch being effectively decapitated? The reaction to the OTL assassination was not exactly cold. I am having difficulties imagining a more severe reaction.
4.) (Slightly less important but) where would McCormack have been around the time of the assassination?