Four of the 44 men who have thus far been president have been shot to death while in office. Two, James A. Garfield and William McKinley, did not make an impression, and are largely forgotten. Two others, John F. Kennedy and Abraham Lincoln, did, and are not.

Shot on Good Friday, Lincoln, of course, is a secular saint — Clinton Rossiter called him "the martyred Christ of the passion play of democracy" — and is viewed as being something quite close to a biblical figure.

Kennedy, much younger, and far from a saint, lives on for a quite different reason: Kennedy, along with Theodore Roosevelt, form a small club of two, the two presidents who broke through to a singular level of public celebrity — known around the world to people indifferent to politics.

They can’t be called "great," as they did not save the country; and while they are not revered, they connect on a whole other level of resonance.

Serious men who did serious things, they are still largely known for their private and family dramas, their internal battles, their personal conflicts, their troubles and woes.

They were our two youngest presidents. Roosevelt was 42 when, as vice president, he succeeded McKinley; Kennedy was 43 when he was elected.

Both came from large, close-knit families with multiple story lines, and led lives that were privileged in the extreme on a great many levels without being easy or soft.

Both were sickly and often bed-ridden as children, during which time they read many books about history. Each one’s family had a "lost" member it struggled to save and whose tale ended badly.

Roosevelt had a brother (Eleanor's father) who was an alcoholic and died young and estranged from his family; Kennedy's sister had intellectual disabilities, though her family struggled to raise her as normal. She lived most of her life in an institution due to complications from a lobotomy.

Each was ravaged by losses while still in his 20's: when Roosevelt was 24, his 22-year-old wife and 48-year-old mother died within hours while in the same household; later, his youngest son, Quentin, was killed in World War I.

Kennedy lost a brother, a sister, a brother-in-law, two shipmates, and many friends in World War II.

Each had characteristics that seem irreconcilable: Kennedy was both a stoic and libertine; Roosevelt was a bleeding-heart conservationist who protected the helpless, and a big-game hunter who dreamed rather too much about war.

Both liked to read and to write about history, knew and liked journalists, understood them, and had them as friends.

Perhaps for this reason, they knew how to play them, marketing themselves and their families for public consumption like no public figures before them, and plying the press of their time with stories and pictures of beautiful women (Alice and Jackie), adorable children (Quentin and John-John), and the requisite number of horses and dogs.

Quentin saluting with the White House guards in the morning presages John crawling under the desk of the president, which is fine as it goes, but does still not explain the intense fascination, which seems to lie in one word: alive.

They lived more intensely than most other people, their friends said, and when you were with them, you were more alive, too.

In politics, this translated into a sense of intense possibility; the sense that history was an adventure that you and they were engaged in, and that it could result in great things.

When the Roosevelt-like Kennedy met a Lincolnesque ending, this presumption was shattered. Which is why we remember the day.

Noemie Emery, a Washington Examiner columnist, is a contributing editor to The Weekly Standard and author of "Great Expectations: The Troubled Lives of Political Families."