(Image credit: Charles Dharapak/AP Photo)

One day after delivering an irascible call to "buy a shotgun!," Vice President Joe Biden today showed his solemn and soft-spoken side as he honored 15 cops and three firefighters for extraordinary courage under fire.

"To me, this is personal. To me you are … the spine of the country," Biden told the recipients of the Medal of Valor, the nation's highest award for public safety officers, and their families.

"You are the heartbeat, the soul, the spine of the nation," he said again.

Biden spoke movingly to the widows of the four medal recipients who paid the ultimate sacrifice, each killed in a hail of gunfire.

"Unfortunately, we have a shared experience. I lost a spouse, I lost a daughter," Biden said, referring to his first wife and one-year-old daughter killed in a car accident in 1972.

"I know this is an incredibly bittersweet moment for you," he continued. "In every one of these occasions, you relive the moment you got the call. You all have a lot more courage than I had some years ago."

"The talk about firefighters and police officers being a family, it's real, it's real," he reassured the survivors.

The most powerful moments of the ceremony came when Biden personally greeted the widows of fallen Sgt. Thomas Baitinger of Florida; Deputies Cameron Justus and William Stiltner of Virginia; and Trooper Joshua Miller of Pennsylvania. Ms. Baitinger sobbed as she embraced Biden before accepting the medal.

The VP's tribute to the heroism of the awardees and their families - in the face of threats from gun violence - comes one day after he provocatively encouraged ownership of shotguns by those who desired extra protection.

"If you want to protect yourself, get a double barreled shotgun," Biden told a questioner during a Facebook town hall on Tuesday. "I promise you, as I told my wife, we live in an area that's wooded and somewhat secluded. I said, Jill, if there's ever a problem, just walk out on the balcony here, walk out, put [up] that double barreled shotgun and fire two blasts outside the house."

White House spokesman Jay Carney today defended the remark, saying it is consistent with the administration's support for Second Amendment gun rights. "The point he was making yesterday," Carney said, "is that in his view, you do not need a military-style assault weapon to protect your home; in fact, you would be better off with a shotgun."

At least one Medal of Valor recipient generally agreed, suggesting guns themselves are not the problem.

"The threat that I faced was somebody carrying a 40 caliber Glock, the exact same firearm I was carrying. It wasn't about a high-powered rifle; it wasn't about high-capacity magazines. It was about somebody wanting to do harm," said Deputy Sheriff Krista McDonald of Washington State after the ceremony.

"It's not about the gun; it's about who's behind the gun," she said.