In an interview with the Pittsburgh Tribune-Review, Wayne LaPierre said law enforcement agencies tend to react after something happens.
"The government has completely abdicated its obligation to protect those people down there, those ranchers," LaPierre said. "They are sitting there, and all they've got when the sun goes down is their gun."
The NRA national meeting begins Thursday in Pittsburgh.
LaPierre also suggested the federal government is making exaggerated claims about guns purchased in the United States being smuggled into Mexico where they end up in the hands of drug gangs.
"A lot of people suspect that somebody in our government, in the Justice Department, in the administration decided to turn the trickle into a river for political advantage," he said.