Who runs the UK?

The US appears to be run by corporations, who provide funds for political parties in elections.
The US TV networks do not carry International news, why not?

Hypothesis:

The population would switch their TV off and not watch the ads.

Discussion:

The UK carries International news, but this does not mean the UK population switches the TV – therefore advertisers are happy to have ads inbetween the sought after evening news slots.

Question:

Does this tells us about the dummying down of the US population v the UK – just still bright enough to follow the news?

So if the corporations run the US, who is running the UK?