The best indicator that the Bush family political dynasty might survive George W. Bush comes from the news that George P. Bush, the president’s nephew, has joined the Naval Reserve. That’s not quite frontline service for the younger Bush although, of course, he could eventually find himself in a hot zone.

But, even if George P. is never anything more than a weekend warrior, he’ll still have given more service than most Americans.

Indeed, what’s most remarkable about the geopolitics of this decade is the huge gap between our military commitment and our actual military effort. That is, President Bush has declared that Iraq, Afghanistan and the overall war against terror and for democracy is “a generational commitment,” “the work of decades.” And yet the nation is curiously unmobilized for this long slog. The total active-duty armed forces number about 1.5 million. And, even when all Guard and Reserve forces are included, the count is still fewer than 3 million. That’s less than 1 percent of the population. By contrast, during World War II, approximately 10 percent of the population was in uniform.

And, during that war, everyone was in. President Roosevelt had four sons, all of whom had significant overseas military assignments.

Yes, allegations of favoritism were sometimes heard, but the family connection seemed to cut both ways. Some of the Roosevelt boys felt they had to prove themselves in battle.

James, for example, led a Marine Raider unit across the Pacific, winning a Navy Cross and Silver Star along the way. Roosevelt’s citation for valor at Makin Atoll in 1943 is notable: “He voluntarily sought out the scene of the heaviest fighting. … His calmness under fire and presence among the foremost elements in the attacking force was a source of inspiration to all ranks.” That’s the sort of leadership that naturally carries over into civilian life. After the war, James was elected five times as a congressman from California.

Admittedly, it didn’t hurt James Roosevelt that he had a famous last name. But the same applies to young George P. Bush, great-grandson of World War I veteran Prescott Bush and, of course, grandson of George H.W. Bush of World War II renown.

An interview that young Bush gave to the Politico, a new Washington newspaper, is revealing: “My grandfather’s my hero,” he declared, skipping over his own father, Jeb, the former governor of Florida, as well as his uncle, the current president. “What really sold me,” he said of his decision to join the Navy, “was having the chance to see the CVN-77 be commissioned under his name.” That would be the USS George H.W. Bush, a Nimitz-class aircraft carrier.

And George H.W. Bush, of course, was as great as anyone in that Greatest Generation. He volunteered to be a Navy pilot while still a teenager; he flew 58 combat missions against the Japanese. So, as president decades later, Bush 41 (for whom I worked) found it easy to rally the country into combat action in Panama in 1989 and Kuwait in 1991. Those conflicts wrapped up quickly. But, had either of them stretched out, that President Bush would have had the personal credibility with the American people to sustain long fighting and to command real sacrifice.

Sadly, that’s what’s needed today. Americans have been brutally reminded that wars don’t always go so well on the battlefield as they do during the PowerPoint presentation in the White House situation room. And yet this President Bush, ex-National Guardsman that he is, doesn’t seem capable of motivating and mobilizing the nation.

Some day, maybe, George P. Bush will be running for office. But he might have to get in line behind those of his generation who have already been to Iraq, such as Pennsylvania’s Patrick Murphy, the first Iraq war veteran elected to Congress. And, by the way, Murphy is a Democrat.