It hasn't always been, writes legal expert.
Does ancient Greek war hawk Pericles provide clues to a besieged Donald Trump's next move? War has always been a helpful distraction for cornered world leaders.
The country's state-run media outlets have been quick to denounce any election meddling talk as anti-Russian hysteria. So what's behind the shift in tone?
If Trump is lying to his own lawyers about Russia, he is risking Bill Clinton's fate.
Presidents past have used this nearly limitless power to halt criminal prosecutions before. What's to stop Trump?
A historian takes us beyond the noise in Washington and examines how US and Russian power and interests compare.
Laws that limit presidential power won't enforce themselves – Congress must act.