Originally derived from Donald Trump’s 2016 pre-catastrophe campaign slogan, "Make America Great Again", it eventually came to be associated with the extremism and hate that Trump, along with other power-hungry individuals, stoked.
It was heavily associated with the attempted insurrection of January 6th, when Trump unleashed a crowd of his supporters in an attempt to overthrow a lawful election and retain the office of the presidency, even as he lost.
Joe Biden and then Kamala Harris, along with others on the left, eventually adopted the term as a label defining those who chose idolatry of an authoritarian narcissist with clear signs of cognitive decline over the defining document of their country, the Constitution.