Allen is forcefully laying out the qualifications of Clinton: "We trust her judgment."
"From the battlefield to the capitals of our allies, friends, and partners, the free peoples of the world look to America as the last best hope for peace and for liberty for all humanity, for we are the greatest country on this planet.
"So we stand before you tonight to endorse Hillary Clinton for President of the United States of America," he says.
Allen says, "I tell you without any hesitation or reservation that Hillary Clinton will be exactly the kind of Commander-in-Chief America needs today. I know this because I served with her. I know this as the former Special Envoy to the Global Coalition against ISIS."
The crowd continues chanting "U.S.A.!"
General John Allen, a retired four-star general of the U.S. Marine Corps who was commander of ISAF forces in Afghanistan, is joined on the stage with former generals and admirals.
"The stakes are enormous. We must not and we could not stand on the sidelines," Allen says.
He says the election could carry the nation to a place of hope or a dark place.
The crowd, and Allen, start chanting, "U.S.A.!"