It’s an unfortunate fact that sometimes an individual’s historic imprint is defined in a snapshot. Such is the case with former Secretary of State Alexander Haig, also a four-star general, who passed away early Saturday in Baltimore. Haig, 85, with an illustrious military career and service as top adviser to three presidents, never lived down an episode of maybe five to 10 minutes, after the 1981 attempt on President Ronald Reagan’s life, when he announced to television cameras that, “As of now, I am in control here in the White House, pending the return of the vice president.” Even the last phrase of the sentence — signaling Haig’s desire to reassure Americans the White House would continue functioning until Vice President George H.W. Bush arrived — is mostly forgotten. The impression that Haig was a usurper of power stuck. Later he wrote in his book, “Caveat,” that he was “guilty of a poor choice of words and optimistic if I had imagined I would be forgiven the imprecision out of respect for the tragedy of the occasion.” Haig, who ran unsuccessfully for president in 1988, was a patriot and public servant whose innumerable contributions are footnote to that moment of imprecision, which indeed is a shame.