Spencer McBride writes on Joseph’s assassination and unlikely election to the Presidency.
Spencer McBride, Joseph Smith for President: The Prophet, the Assassins, and the Fight for American Religious Freedom (Oxford: Oxford University Press, 2021), 195, 207
There is no evidence that Smith was assassinated because he was a presidential candidate. A Smith victory was extremely improbable and the anti-Mormons in Illinois knew it. Inasmuch as political motives were at play in the assassination, they were almost certainly state and local. Smith’s campaign for the country’s highest elected office may have exacerbated these concerns. Illinoisans did not fear that Smith would win the election, but his candidacy may have signaled a level of political ambition that confirmed their belief that Smith would not relent in seeking political power. He became the first assassinated presidential candidate in American history, but he was not assassinated to prevent his election.
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However, elevating the Mormon past to a more accurate place in United States history does not mean elevating Smith’s presidential candidacy to the point that we depict him as a serious contender in 1844. From the outset, Smith’s presidential prospects were bleak; there was virtually no chance that he would beat his Democratic and Whig rivals. Indeed, Smith and other church leaders were hesitant to put all their eggs in the presidential basket. The presidency was always just one potential solution to the Mormons’ problems.