Assassinations:
President: Abraham Lincoln (R)
Assassin: John Wilkes Booth
Political identity and motive:
Booth was a Democrat, angry that Lincoln had freed the slaves and preserved the Union.
President: James A. Garfield (R)
Assassin: Charles J. Guiteau
Political identity and motive:
Guiteau was frustrated that he did not receive a political appointment in the Garfield administration, and he believed "that God had commanded him to kill the ungrateful President." Since we can assume that God did not, in fact, command him in this way, we must deem Guiteau mentally unstable.
President: William McKinley (R)
Assassin: Leon Czolgosz
Political identity and motive:
Czolgosz was an anarchist who believed that "there was a great injustice in American society, an inequality which allowed the wealthy to enrich themselves by exploiting the poor," and that he had to do something about it. Mimicking the assassination of King Umberto I of Italy, done for similar reasons, he shot and killed McKinley. Oddly, Czolgosz had earlier voted Republican, but the assassination motive was clearly as described above.
President: John F. Kennedy (D)
Assassin: Lee Harvey Oswald
Political identity and motive:
Defector to the USSR. Earlier attempted to kill General Edwin Walker, who was "an outspoken anti-communist, segregationist and member of the John Birch Society." Controversy about the assassination continues to persist, and Oswald was killed before any real digging could be done, so we are primarily left with his identity (as a defector to the USSR) as the prime indicator.
Attempts:
President: Andrew Jackson (D)
Would-be assassin: Richard Lawrence
Political identity and motive:
Lawrence was mentally ill, suffering from polymorphous delusions.
President: Theodore Roosevelt (R and Bull Moose)
Would-be assassin: John F. Schrank
Political identity and motive:
Schrank was mentally ill; he claimed "that it was the ghost of William McKinley that told him to perform the act."
President: Franklin D. Roosevelt (D)
Would-be assassin: Giuseppe Zangara
Political identity and motive:
"In the Dade County Courthouse jail, Zangara confessed and stated: 'I have the gun in my hand. I kill kings and presidents first and next all capitalists.'" From Zangara's own words, much can be taken. However, he may also have been mentally ill. (Perhaps anyone who wants to kill a president is a touch deranged.)
President: Harry S Truman (D)
Would-be assassin: Oscar Collazo and Griselio Torresola
Political identity and motive:
Oscar Collazo and Griselio Torresola were members of the Puerto Rican Nationalist Party. Puerto Rican Nationalists, represented by Marxist terrorist groups such as FALN, who were responsible for scores of bombings in the U.S.; they were arguably the most active terrorist group in U.S. history. (Interesting side notes: President Carter freed Collazo in 1979, and President Clinton pardoned several FALN terrorists. Il n'y a aucun ennemi du cote gauche?)
President: John F. Kennedy (D)
Would-be assassin: Richard Paul Pavlick
Political identity and motive:
Pavlick was anti-Catholic, and he was also upset by "the close 1960 U.S. Presidential election, in which Kennedy had defeated Republican Richard Nixon by 118,000 votes." However, "Judge Emmet C. Choate ruled that Pavlick was unable to distinguish between right and wrong in his actions." He was kept in a mental hospital for three years. Will this be the closest we get....?
President: Richard M. Nixon (R)
Would-be assassin: Arthur Bremer
Political identity and motive:
Bremer is an interesting case, one that would require more research than we're doing in this admittedly surface analysis. He hated Nixon, but apparently, he also hated segregation and bigotry, and he did shoot Democratic candidate George Wallace. He also clearly had mental instability. Why did he hate Nixon, and also Wallace? He stated "It is my personal plan to assassinate by pistol either Richard Nixon or George Wallace," and that his purpose was "to do SOMETHING BOLD AND DRAMATIC, FORCEFUL & DYNAMIC, A STATEMENT of my manhood for the world to see." These are deep waters, and we'll have to give this one a pass for now.
President: Richard M. Nixon (R)
Would-be assassin: Samuel Byck
Political identity and motive:
Byck "began to harbor the belief that the government was conspiring to oppress the poor." He attempted to join the Black Panthers. However, he was also "diagnosed with manic depression, a mental disorder characterized by both depressive 'lows' and (less frequently) manic or euphoric 'highs.'" He had left-wing motives, but he was also mentally unstable.
President: Gerald R. Ford (R)
Would-be assassin: Lynette Fromme
Political identity and motive:
Insane member of the insane Manson Family.
President: Gerald R. Ford (R)
Would-be assassin: Sara Jane Moore
Political identity and motive:
Revolutionary leftist political activist.
President: James E. Carter (D)
Would-be assassin: Raymond Lee Harvey
Political identity and motive:
Harvey was possibly mentally ill, but also, charges were dismissed for lack of evidence. This one doesn't count.
President: Ronald Reagan (R)
Would-be assassin: John Hinckley, Jr.
Political identity and motive:
Mentally ill, no apparent political motive (despite some absurd references to his connections to the Bush family).
President: George H.W. Bush (R)
Would-be assassin: Operation of sixteen men working for Saddam Hussein's Iraq
Political identity and motive:
Geopolitical attack/act of war.
President: Bill Clinton (D)
Would-be assassin: Francisco Martin Duran
Political identity and motive:
From Wikipedia:
"Duran pleaded not guilty and mounted an insanity defense, claiming that he was trying to save the world by destroying an alien 'mist,' connected by an umbilical cord to an alien in the Colorado mountains. He also claimed to be incited by conservative talk show host Chuck Baker, who spoke on air about 'armed revolution' and 'cleansing' of the government.
In both cases, these are claims made by Duran. We would need more external information to make a judgment.
President: George W. Bush (R)
Would-be assassin: Vladimir Arutyunian
Political identity and motive:
Georgian national who threw a grenade towards President Bush. Not quite sure yet what his motivation was. Pass for now.
Totals:
Clearly mentally ill (5)
Guiteau
Lawrence
Schrank
Fromme
Hinckley, Jr.
Anti-catholic (and possible Republican) motivation, coupled with mental illness (1):
Pavlick
Left-wing motivations, coupled with mental illness (1):
Byck
Unclear/more info required/weak evidence--pass (4):
Bremer
Harvey
Duran
Arutyunian
Left-leaning political motivation (7):
Booth
Czolgosz
Oswald
Zangara
Collazo
Torresola
Moore