The murder of an actual (or potential) head of state often is followed by conspiracy theories.
Some killings (or attempts) may be apolitical. Shooting Ronald Reagan and George Wallace were the results of tormented minds not bothered by any ideological nuances.
In some recent cases, the matter is rather simple. The Ceausescus were bloodthirsty vermin who needed be allowed no opportunity for a second chance. Allende was a Marxist who was parlaying an electoral fluke into one-man misrule.
If we go back in history, we find some more mysterious killings. The Emperor Napoleon died in exile while under control of English authorities. Evidence points to a death hastened by (or the direct result of) poison with a cumulative effect.. It would be so simple to blame the English for his demise. However, a live Bonaparte was an advantage to an England not wholly in agreement with French world policies. He was a potential instrument of destabilization. Only French interests would be served by his early demise. A dead person can become a martyr, and the French exploitation of Joan of Arc should not be forgotten.
Warlord/dictator Francisco Franco was known to have allowed one of his allies to be executed even though a rescue attempt might have saved him. When an ally could turn to a future rival, martyrdom provides a more useful symbolic ally.
We may never cease hearing of conspiracy theories about the deaths of Lincoln and Kennedy.
The situation in Pakistan is complex. The dictator is a regional friend whose actions are limited by circumstances. His initial coup was beneficial as it denied radical theocrats closer access to deliverable nuclear weapons.
The return of Bhutto to the political scene should not be seen as the restoration of political reform but as the effort of a corrupt family to get a prime place at the trough. The husband of the late candidate was not called Mr. Ten Percent for nothing.
In terms of our domestic politics, there was a certain imperative of giving lip service to the return of Bhutto to the public scene in Islamabad. Yet what overarching role did she serve?
Her own supporters would have little reason to see her dead. Her movement was dominated by a personality rather than a set of ideals. In a three-way contest, she would assure a majority vote for the radical theocrats. Thus, her abrupt removal from the scene would benefit Musharraf. However, the price in international public opinion (especially from the United States) would be very dear and the current leader is driven more by logic than superstition. Those who stood to gain the most by her presence as an electoral factor are not known for consistently rational thought. The very thought of a woman on the public stage is appalling and demands direct and violent action, in spite of the short-term negative effects. Killing her helps to stir up violence by her supporters against the Government. Chaos benefits the radicals.