Canada

Take anything a leader says seriously, and at full value. They represent a group, even if that group would rather they not do so, as they hold power to bring what they say at least a little closer to reality (or burn their constituency trying). Just because they say "oh, I'm just joking BTW" afterwards, doesn't mean that they weren't serious at the time and intended to do their best to make it reality before receiving backlash or something.

Anything Trump says should be treated as if he has already signed an executive order to make it happen. If he won't take responsibility for his own words, he should be made to by others, because words, even the most absurd and casually said ones, carry the power of office, and reveals at least a part of the leader's actual intent.

It is in not taking such words seriously that so many tragedies have happened over the course of history. These days, rhetoric is sounding eerily close to those said back in the 1930s, and I don't mean only those from one southern madman. Many of our own leaders spend all their time and effort deflecting and blaming others for their own failings.

Fail to learn from history, and you fail to prevent its repetition.