While cable news pundits love to talk about patriotism, substantive dialogue is usually lost in raging debates over lapel pins and stars and stripes backdrops. Moving beyond partisan rancor, America’s commitment to ensuring our men and women in uniform get the care and benefits they deserve speaks volumes about our priorities as a nation. More pragmatically, for an all-volunteer military to sustain itself we need to make the armed forces a more attractive employment option.

This is why the “New G.I. Bill” is so critical for the 21st century. Having passed through Congress with overwhelming bipartisan support, the bill is a substantive way for Americans to show our commitment to those who have sacrificed for our country as well as a powerful incentive to young men and women considering military service.

Earlier this month, the president threatened to veto this expansion of one of the most successful pieces of legislation of the 20th century. Faced with veto-proof majorities in the House and Senate, the White House is now backing off what would have been a dereliction of duty. Whether it’s the dismal conditions at Walter Reed or the refusal to provide adequate care for combat veterans suffering from post traumatic stress disorder, the failure of the current administration to take care of our heroes is not only tragic, but a moral outrage.

The New G.I. Bill seeks to fulfill the promise America made to our veterans following World War II. The original Servicemen’s Readjustment Act of 1944 honored veterans by providing free tuition, books, and a living stipend to nearly 8 million returning service members. For every dollar that was spent on the original G.I. Bill, seven dollars came back to the national economy through consumer spending, tax revenue, and productivity. In other words, the G.I. Bill is one of the greatest investments America has ever made.

Unfortunately, the benefit has not kept up with the times. Our returning veterans are now forced to pay up to 40% of the cost of a public university. For elite private universities, it amounts to a fraction of the total cost. And not surprisingly — given their subpar treatment in areas from body armor to health care — National Guardsmen and Reservists who serve in Iraq and Afghanistan are getting only a portion of the benefits of active duty service members, even though they serve longer tours than anyone else.

The new G.I. Bill changes that. The Post 9/11 Veterans Education Assistance Act, passed overwhelmingly by both houses of Congress last month, would cover tuition at a rate comparable to the highest tuition at a state school in which a veteran is enrolled. The legislation would also extend the benefit to activated Guardsman and Reservists who serve longer than three months in Iraq or Afghanistan. The cost of the bill is between $2.5 and $4 billion per year — less than we spend in Iraq in a week.

Although the bill has broad bipartisan support, there are opponents. President Bush, whose father graduated from Yale as a recipient of the original G.I. Bill, is opposed to the legislation because he claims it will hurt retention rates. Senator McCain also opposes the bill for the same reason.

The fact is this expanded benefit will act as a powerful incentive to attract people to the military and keep them there once they’re in uniform. Polling among new recruits shows that the G.I. Bill is the military’s single most effective recruiting tool. In my personal experience as an officer in the U.S. Navy, the number one reason the enlisted men and women I served with signed up for the military was “to get money for college.”

The fight for this critical legislation has been led by members of the Senate who have experienced the sacrifice of combat first-hand, including Jim Webb, a Democrat of Virginia; Chuck Hagel, a Republican of Nebraska; John Warner, a Republican of Virginia; and Frank Lautenberg, a Democrat of New Jersey. Having served their nation in uniform, these leaders understand the debt America owes the next greatest generation.

At a time when our nation should be doing all we can to promote service and support the sacrifice of our veterans, we owe our veterans more than lapel pins and “Support Our Troops” bumper stickers. It’s time for the president to do right by our veterans, and sign this New G.I. Bill for the 21st century into law.

Mr. Kauffmann is a fellow at the Truman National Security Project and a vice president at the Glover Park Group in New York. Between 2002 and 2007, he served as an officer in the U.S. Navy.