1907: [US] Congress bans direct contributions to candidates from corporations.

1947: Congress expands restrictions by barring corporations and unions from using funds from their general treasuries to support candidates, which would include advertising to help a candidate, for example.

That history may soon change:

More than 100 years of restrictions on corporate support of political candidates will be at stake next week when the [US] Supreme Court considers … casting aside previous rulings that uphold laws restricting corporate support of political candidates.  The court ruled in 1990 that corporations, because of their “immense aggregations of wealth,” possessed a unique ability to drown out the voices of individuals in the nation’s political conversation. That precedent was reinforced in 2003 when the court upheld the federal campaign finance law that limits the electoral influence of corporations, unions and special interest groups.

Politicians are grateful to and beholden to whomever convinces voters to elect them.  This is an inescapable feature of democracy; whoever can persuade voters becomes a power behind the throne.  Once upon a time some sort of pundits persuaded US voters that non-media firms are too persuasive; if those firms were allowed to try to persuade voters they would succeed in doing so and gain power thereby.  And this was somehow bad.  So voters let politicians ban non-media firms from trying to persuade voters in elections.

The pundits who are still allowed to try to persuade voters still do so, and they are now the powers behind the throne.  They continue to convince most of us that we should not be allowed to listen to non-media firms, regarding elections or off-label drug uses.  We believe those we are allowed to hear when they tell us that we should not be allowed to hear the corrupting voices of certain others.

But what if history had gone the other way?  What if it had been regular firms who had persuaded us that we should not be allowed to listen to the corrupting influence of activists, interest groups, academics, or media pundits?  Those now familiar voices would instead have been silenced and we would now instead be persuaded by firms, not only regarding elections but also regarding who can be trusted to have a voice in elections.  We might again have believed those we were allowed to hear when they told us we should not be allowed to hear the corrupting voices of certain others.

The more plausible is this alternative history scenario, the more you should wonder how sure you can be that your history is right and that alternate history would have been wrong about who should be allowed to persuade voters.   Yes humans may be biased to listen too much to certain sources, but you should expect the sources you are now allowed to hear to be biased to point the accusing finger at other sources, and not themselves.

In a third alternate history, all these voices would be allowed to persuade voters in elections.  And some sources would end up being the most persuasive in this scenario, earning their position as the biggest powers behind the throne.   Standing outside all these different histories, what reason do we have to think that these sources that would win in a full open contest do not deserve to be heard?

Added:  In another alternate history firms were allowed to persuade voters, but only in Latin or Esperanto.   Communicating well takes effort; allowing talk but forbidding effort to talk is pretty much forbidding to talk.