Final answer:
Barack Obama publicly humiliated Donald Trump during the White House Correspondents' Dinner in 2011. This event played a role in shaping the relationship between the two and influenced Trump's decision to run for president.
Step-by-step explanation:
In 2011, Barack Obama publicly humiliated Donald Trump during the White House Correspondents' Dinner. During his speech, Obama made jokes about Trump's presidential ambitions and his role in promoting the conspiracy theory that Obama was not born in the United States. This public humiliation was seen as a significant event in the relationship between Obama and Trump, and it helped fuel Trump's desire to run for president and seek revenge against Obama.
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