Before Thursday, President Barack Obama had issued only a brief written statement about the events in Ferguson, Mo., a St. Louis suburb that erupted in protests after Saturday’s killing of an unarmed black youth, Michael Brown, by a police officer.

But he soon came under pressure to address events there more forcefully, prompting him to interrupt his vacation in order to make a public statement today.

In the modern era, we expect presidents to weigh in on almost every major news story – an impulse that reflects our desire for them to appear to be in control of events. Mr. Obama accordingly noted today that he had directed the Justice Department to investigate the shooting in Ferguson, but the agency’s response was already underway before the statement. His comments thus seemed intended instead to alleviate concerns that he was not taking what had happened seriously enough.