President Barack Obama’s planned reductions in defense spending have earned him considerable criticism from the right. One of his potential Republican challengers, Mitt Romney, laments that the United States Navy “is smaller than it’s been since 1917.” Other conservatives claim that the cuts in military spending will put the nation at risk.

The “cuts,” worth nearly $900 billion over the next ten years, won’t necessarily reduce spending from today’s $671 billion defense budget. Rather, they will reduce projected increases in spending. Part of the reduction will happen if America winds down its engagement in Afghanistan in 2014. For 2012, the Pentagon has requested $118 billion for overseas military operation, the bulk of which is to finance the Afghan war.

Former defense secretary Robert Gates identified some $400 billion more in savings, largely in organization and procurement. He capped production of the new F-22 fighter jet for instance, much to the dismay of national-security hawks in Congress.

Yet it’s because of Congress’ failure to find cuts elsewhere that the Defense Department faces an additional half a trillion dollars worth of reductions.

In budget negotiations last year, Democrats and Republicans failed to agree on a plan for long-term fiscal consolidation. As a result, some $500 billion in automated cuts was enacted.

Defense secretary Leon Panetta, Gates’ successor, had forecast “doomsday” if the sequester cuts were to come into effect. The American military would be reduced to a “paper tiger,” he said, one that “invites aggression.”

Whatever the effect on the military’s ability to project power, even with the $500 billion in additional savings, the defense budget will not shrink in real terms but remain stagnant for the next ten years.

Since September 11, 2001, defense spending has increased by almost 7 percent a year, up from $291 billion ten years ago. The Congressional Budget Office estimated last year that in order for the military to execute its base budget plans for this decade, it needed a total of $597 billion or 11 percent more than if funding was held at the 2011 level. Military spending would thus rise by almost $60 billion a year on average unless entire weapons programs were reconsidered or pay and benefits for servicemen and -women was reduced.

As procurement costs rise because weapons system are ever more sophisticated, there will have to be reductions in the force to accommodate the budget squeeze. Army and Marine Corps will lose troops as the strategic emphasis shifts to the Pacific realm where air and sea power are deemed critical.

It’s because of this “Asia pivot” that the conservative Heritage Foundation’s Brian Slattery questions the wisdom of not having a more robust navy. “The American fleet, amid a host of defense issues in need of attention, cannot atrophy any further,” he believes. Among those issues; China’s “increasing efforts to assert its ‘indisputable sovereignty’ over the South China Sea.”

If President Obama wishes to follow through on pledges of a greater Pacific presence, he must either somehow overturn much of the defense slashing he has implemented or attempt to loot other defense accounts to fund a sustainable blue water navy.

In real terms, the US Navy has diminished in size from nearly six hundred ships at the end of the Cold War in 1989 to 283 in 2009. Under current plans, the force could approach the number of 245 ships that were in service before the United States joined the First World War in 1916.

Before it faced the $500 billion in sequestered cuts, the Pentagon envisioned buying 275 new ships over the next thirty years at a total cost of $465 billion — although the Congressional Budget Office estimated that the cost would be closer to $539 billion through 2041, about 16 percent more.

More than two hundred of those ships would be for combat with seventy for logistics and support missions. Given the rate at which the Navy planned to retire ships from the fleet, the total number in service would remain over three hundred throughout the thirty years period.

It’s unclear how the additional $500 billion in reductions will impact long-term procurement although the Pentagon announced Wednesday that it plans to cut sixteen ships from its five year budget plans which would reduce the number of new ships funded in fiscal 2013 by three, from thirteen down to ten.

Secretary Panetta, moreover, insists that whatever the size of the cuts, the navy will maintain its eleven carrier strike groups with the newest aircraft carrier, USS Gerald R. Ford, scheduled to replace the USS Enterprise in 2015.

It seems altogether unlikely that the fleet will approach 1917 levels. Even if it did, it must be noted that simply counting the number of ships gives one a poor indication of American naval power. The vessels that are in service with the United States Navy today are among the most sophisticated (and most expensive) in the world. Numbers matter less than capacity and in this regard, the United States military is — and will for decades remain — unparalleled.