Biden vs. Trump: Which one is guilty of "bribery"?

If you have read that, perhaps your reaction was, “then why isn’t every politician already in jail?” The problem is that politics is inherently corrupt. Even if a politician is not “on the take” for personal money, it goes without saying that every incumbent politician regularly uses the powers of his office to obtain intangible political benefits to himself from third parties, for use against rivals. Every such action will also be justified as in some way benefiting the public. But is obtaining something of political advantage against rivals enough to make the exercising of government authority a crime, even where nothing tangible goes to the politician directly?

Take some examples. The teachers union contributes millions to campaigns of New York politicians, and delivers votes by the hundreds of thousands, and in return charter schools are restricted and teacher pensions are increased (official acts), all in the name of “helping our public schools.” Bribery? Politician gives foreign aid to Africa (official act) and in return African country agrees to buy tractors from Caterpillar; politician then uses the African purchase by going to Caterpillar factory and proclaiming great success “bringing manufacturing jobs home,” resulting in thousands of additional votes. Bribery?