"THEY" didn't. If you mean US politicians or US deep state.
The person who arranged the hit is the one who has the most to lose, including his life.
It is someone who had cooperation from US politicians and deep state, mostly by having them do nothing.
Who has tons of money to use for this purpose ? Who has a team of skilled snipers at his beck and call? Who has diplomatic immunity and is not subject to our Justice System ? Who will lose EVERYTHING and likely be killed by his own citizens ?
Here's a hint:
