Whether Trump was alive or not was no longer relevant to the UA.
Even if Washington and Lincoln crawled out from their coffin, it would be difficult to save the situation faced by the country at this moment, let alone someone with no experience in politics.
However, the situation was different for Celestial Trade.
A reasonable explanation or excuse could legitimize the aggression and settle the sequelae left over from the war.
While it was not difficult for Celestial Trade to use its technology to create an identical Trump, humans after all were inseparable from society. Even a perfect AI would face many obstacles during the integration of society.
In the short term, this proposal could be flawless, but it would inevitably create problems down the road. In Jiang Chen's blueprint of Earth Federation, this kind of risk could not be tolerated. He didn't want to solve a historical problem during the final battle with Harmony.