LONDON — The marathon course here at these 2017 IAAF world championships started and finished at Tower Bridge. Just a few steps away, of course, is Tower Hill, where the likes of Anne Boleyn met her fate.

It’s fascinating, those historical and cultural markers that, in turn, frame — consciously or otherwise — national identity.

In Britain, one might argue, right is right, wrong is wrong, rules are rules, black is black, white is white. When you make a mistake, it’s off with your head. You wonder why the Pilgrims wanted out? The United States, by definition, is a land of second chances. The American national narrative  — the founding national story, told over and again — is redemption.

To be clear: find fault all you want with these oversimplifications. Detail, if you please, the countless exceptions.