This idiom or expression like question means:

I agree.
I really agree.
That is the truth.
That is exactly the truth.

This idiom or expression like phrase has to do with:

Telling the truth.

When someone says “Clinton came clean on Monica,” they mean “He told the truth about the Monica incident.”

This idiom or expression refers to:

Something used for hiding the truth.

Politicians always use smoke screens. They exaggerate about unimportant things to avoid dealing with the real issues.

This idiom or expression means:

Exaggerating.
Overstating the facts.

This idiom or expression means:

Tell me the truth, or you’ll be sorry.
Tell me the truth, or you’ll have to suffer the consequence.
Do you want to tell me the truth? Because otherwise there will be consequences.