John McCain is faulting both Republicans and Democrats on their efforts to control the proliferation of nuclear weapons.
The likely Republican presidential nominee favors an approach that doesn't rely too heavily on either direct talks or military force to reduce the spread of nuclear weapons.
McCain spoke on the issue Tuesday at the University of Denver.
He said: "If you look back over the past two decades, I don't think any of us, Republican or Democrat, can take much satisfaction in what we've accomplished to control nuclear proliferation."
As he talked, anti-war protesters interrupted him four times. They stood up and yelled "Stop this war" before the crowd tried to drown them out and they were escorted out.