In 2011, Martin McGuinness, the former leader of the Provisional IRA (Irish Republican Army), ran for president of the Republic of Ireland. Over the four decades of his public life, McGuinness had moved from supporting terrorism, including assassination, for political ends to pursuing votes through the ballot box. Some now feted him as a "peacemaker." But to many voters, his personal journey from the use of violence to the use of democratic means to achieve a united Ireland still seemed like a work in progress.

During one televised presidential debate, the moderator for the Irish public broadcaster RTÉ, Miriam O'Callaghan, asked the candidate: "How do you square, Martin McGuinness, with your God, the fact that you were involved in the murder of so many people?" McGuinness called it a "disgraceful comment." But the blow landed. Worse for McGuinness was that, after the cameras turned off, he took O'Callaghan into a side-room, where she was seen leaving five minutes later "badly shaken." The Irish electorate did not take well to the news that a broadcaster and mother of young children had been treated in such a way. McGuinness's run for the presidency failed.

The episode mattered because McGuinness still lived in the gray zone of political violence: not fully condoning it, but not fully condemning it, either—especially when it served his cause or came from his supporters. Some Americans have now entered this same gray zone. Parts of the U.S. Left have inhabited it for years.

Many commentators have pointed to the difference in responses between the killing of George Floyd and that of Charlie Kirk. Floyd's death led to a summer of violence, burnings, and lootings, behavior often excused by Democratic lawmakers. Groups like Antifa shut down American cities night after night with minimal official condemnation in the summer of 2020. By contrast, Kirk's death, so far, has led to dignified and mournful prayer meetings. If the American Right were ever to erupt into violence, then it would face its own moment of challenge.

Meantime, the American Left has the bigger questions to answer. In recent days, portions of the Left have expressed greater outrage about Jimmy Kimmel's brief absence from his late-night talk show on ABC than Kirk's absence from life. Others—up to and including members of Congress—have suggested that Kirk's words constituted violence, and that therefore condemnations of the violence directed against him require a certain caveat. Such slips became possible only because the American Left has been increasingly drawn to the gray zone.