Prince William County Police Chief Stephan Hudson, left, speaks during a news conference next to a picture of Officer Ashley Guindon, who was killed on Saturday. (Jose Luis Magana/Associated Press)

AT LEAST 14 police officers have been killed in the line of duty across the United States this year. Officer Ashley M. Guindon , of the Prince William County Police Department, who died Saturday, was the latest. All those deaths are tragedies for their departments, their communities, and their families and friends.

Officer Guindon, 28, died just a day after she’d been sworn in as a brand-new officer. She was the first female officer to be killed on the job this year, and without a doubt the least experienced; the other 13 had an average of more than 16 years in uniform.

But no amount of experience would have immunized Officer Guindon from the gunfire that struck her down late Saturday, when she responded to a domestic-disturbance call along with two veteran officers. All three were shot as they approached or tried to gain entrance to a single-family house in Woodbridge. The alleged gunman, Army Staff Sgt. Ronald Williams Hamilton, who works at the Pentagon, apparently opened fire without warning and at close range. Inside the house, his wife, Crystal Hamilton, had already been shot to death, police said.

The other two officers who were injured — Jesse Hempen, 31, and David McKeown, 33 — had been on the force for eight and 10 years, respectively. In all likelihood, they had responded to many such domestic calls. As police officers do everywhere, they had risked danger again and again in the course of their daily duties. They had come away unscathed, until Saturday.

Many Americans have been demanding more accountability from law enforcement, especially since the shooting death of a young black man in Ferguson, Mo., in August 2014. They are well within their rights to do so, and police departments nationwide would do well to heed those demands.

Americans would also do well to bear in mind the array of perils that officers manage and confront regularly — and with professional competence and personal courage so much of the time. Counties, cities and neighborhoods rely on police for that expertise and proficiency, and rarely remark on it. It is an assumed necessity, a sine qua non of a civilized society. We take men and women in uniform, as well as the hazards they encounter, as givens.

That’s a mistake, as Officer Guindon’s unwarranted death reminds us. Police and other law enforcement officers take an oath to serve and protect; implicit in that is that they willingly take risks, and often enormous ones, that the rest of us would be loath to face.

Officer Guindon was young, eager, ambitious, passionate about police work, admired as “a professor’s dream” by one who taught her in college. The people in Prince William, as all of us, are poorer for her loss, and indebted to her and others who serve and protect.