Donald Trump speaks during a campaign rally in Greensboro, N.C., on June 14. (Chuck Burton/Associated Press)

In his July 17 Business commentary, “Trump’s most enduring — and unbefitting — trait,” Allan Sloan built a credible case for presumptive Republican presidential nominee Donald Trump’s unsuitability for the presidency based on his most consequential character flaw: a lack of impulse control. Pointing to past presidents, Mr. Sloan illustrated the monumental global consequences of having a president who cannot control his impulses.

When Mr. Trump announced his candidacy, I joked that he embodied our country’s collective id. The id was what Freud described as the psychological force that seeks immediate gratification of any impulse. I did not think Mr. Trump’s campaign would survive the month. Like many, I was blind to the country’s shadow side. In psychology, the shadow is a perceived personal deficiency, so personally repugnant that we often project it onto others as a way of distancing us from what we cannot face in ourselves.

Mr. Trump may have done the country a service by revealing our shadow side. But how will we manage our shadow now that we are confronted with it? Even if Mr. Trump loses, his supporters will remain. Now that they’ve been given oxygen, ignoring and rejecting them will result in more dysfunctional behavior. How may we use awareness of our shadow side to grow and mature as a country?

And, should Mr. Trump win, how many U.S. emigrants can Canada accommodate?

Penny Potter, Mason Neck