When a country like the U.S. maintains an enormous trade deficit for decades, it’s not as if that money goes overseas and disappears. It has to come back to the U.S. in some form, and foreigners know damn well that buying U.S. politicians is one of the cheapest and most profitable investments they’ll ever make.
It works domestically as well. See Solyndra and many others. Just think for a few hundred thousand, they were able to secure $535M.
The congress vermin are willing to sell their country out for so very little.