When members of the Newtown police force entered the school auditorium where President Obama was about to speak, the crowd rose and applauded. The officers’ quick response to the carnage at Sandy Hook Elementary School had probably saved many young lives.

As the nation starts debating the lessons of Newtown, where a gunman killed 26 people, including 20 children, we should listen to what law enforcement officers have to say. Their message is clear and consistent: Tighten gun control laws.

The National Rifle Association likes to depict gun control advocates as liberal loonies who don’t respect or understand red-blooded, heat-packing Americans. But that characterization has always been unfair. The men and women who patrol our streets every day are the loudest advocates for greater restrictions on gun ownership.

Listen to James Johnson, the police chief of Baltimore County, Md., and the new chairman of the National Law Enforcement Partnership to Prevent Gun Violence: “America, we are not doing enough to keep guns out of the wrong hands. We are long past the point of saying ‘enough is enough.’ The mantra has grown old. It’s time to take action to keep firearms from dangerous people.”

No law can protect every child — or every cop — from a crazy person with a gun. But it’s absurd and even immoral to assert, as the gun lobby does, that because laws are imperfect, they are useless.