There are a lot of theories about the attempted assassination of Pope John Paul lI in 1981. One is that the KGB, acting through Bulgarian and East German intelligence agencies, directed the assassination attempt, motivated by their fear of the Solidarity movement in Poland and the Pope’s energizing effect on Polish dissent.
The Pope does, strictly speaking, qualify as the leader of a country, being the monarch of the Vatican City State, although I suspect he doesn’t pay that much attention to the mundane business of governing the city.
Augusto Pinochet was aided by the US in the coup to take control of Chile away from Salvatore Allende, which resulted in Allende’s death. The official story is that Allende committed suicide by shooting himself in the head numerous times but assassination has long been suspected. The suicide was claimed to be done by firing an AK47 in automatic mode, so not totally ridiculous, but assassination story crops up from time to time.
Boris III of Bulgaria in 1943? Allied with Hitler, died mysteriously after refusal of sending troops to aid the Reich in USSR and deporting Bulgarian Jews and trying to ease a way out of the war with the Allies.
Another not-quite-official and not-quite-head-of-state (but with the most disastrous consequences) assassination: the murder of Archduke Franz Ferdinand in 1914. The organisers in the Serbian Black Hand were highly connected and influential in Serbian governmental circles, even if this specific act was not known in advance to the Serbian government.
I recall reading that there was a plan floated by young British diplomats to assassinate Hitler by a marksman - in the 1930’s. The planning went so far as to have a team member find an apartment that overlooked a place where Hitler frequently appeared. But - unfortunately “cooler heads prevailed”.
Unfortunately I cannot find a cite. While searching for one I turned up this cite about Pope Pius XII that, if true, would fit the Original Poster’s description:
You know that never works. The assassin turns into Hitler, or someone worse than Hitler takes over, or it turns out he’s in the universe where Hitler was actually good and when he returns to his own universe the world is nothing but a desolate wasteland. Best they didn’t actually try to do it.
That, plus the Soviets would of course have known that Kennedy would, after the assassination, be succeeded by Johnson. There’s not much reason to believe that from the Soviet perspective, Johnson in the White House would have been preferable over Kennedy. He was quite the cold warrior in the early space race, for instance.
I recall reading that there was a plan floated by young British diplomats to assassinate Hitler by a marksman - in the 1930’s. The planning went so far as to have a team member find an apartment that overlooked a place where Hitler frequently appeared. But - unfortunately “cooler heads prevailed”. Unfortunately I cannot find a cite.
The OP didn’t rule out killing enemy heads of state in times of war. Much more common back when kings lead their armies into battle and gunners could be instructed to hit the biggest, prettiest tent in the opposite camp. In 1918, alarmed by the Germans’ initial success in Operation Michael, the French realized that the Kaiser was staying at a chateau within bomber range. The British obliged with the actual attack, which missed the chateau building as well as the Kaiser himself, since he’d left the day before.
First of all, “the Silent” is a badass nickname. Very Clint Eastwood-y.
Second of all, William of Orange was one of the most important people of his era and the founding father of the Netherlands, so I suppose he was intimidating, especially to the Spanish.
