None of America's armed forces can meet all of the demands placed on them by commanders today.

Just last week, the U.S. Navy said that for the second time in seven months, equipment failure prevented an amphibious assault ship - the USS Essex - from meeting a commitment at sea.

Unfortunately, this is not surprising. The U.S. military faces a readiness crisis - one confronting not just its people and end-strength cuts - but pushing equipment to the breaking point. Across all services, long-standing readiness problems are worsening and breakdowns are happening more frequently.

Adm. Jonathan W. Greenert testifying to Congress last July shortly before his promotion to Chief of Naval Operations, said: "The stress on the force is real. And it has been relentless."

The overall picture is dismal: While the Navy's fleet has shrunk by about 15 percent since 1998, the number of ships deployed overseas has remained constant. Each ship goes to sea longer and more often, resulting in debilitating maintenance problems.

Simple wear and tear is weakening defense capabilities across the board as the military's major platforms age after high wartime usage rates and a lack of major recapitalization since the Reagan buildup.

An Air Force F-15C literally broke in half during flight some years ago. Today, every single Navy cruiser hull has cracks; A-10C Warthogs have fuselage fractures, and the UH-1N Twin Huey helicopter fleet is regularly grounded. Over half the Navy's deployed aircraft are not ready for combat.

Last April, the engine of a F/A-18C Hornet caught fire aboard the USS Carl Vinson. Last March, the engine of a Marine Hornet about to take off from the USS John C. Stennis exploded as it was about to take off.

As these aging aircraft were bursting into flames, senior officials were warning Washington politicians that keeping the older fighter planes in safe flying condition was "one of their most serious challenges."

Built in the 1980s and 1990s, the jets were designed to fly for 6,000 hours. Delayed delivery of the replacement F-35, however, has forced the services to squeeze an additional 4,000 flight hours out of the Hornets.

This is just a sample of the readiness problems plaguing those who serve in uniform. Yet, the almost-$1 trillion "stimulus" bill didn't contain a nickel for military modernization. Instead, the president and Congress have been cutting defense dollars and capabilities for the past three years.

Today, Washington wants to divert even more defense dollars to debt reduction - even in the face of the rapidly declining readiness of the U.S. military. This will only exacerbate the problem of how to meet the urgent need to conduct overdue maintenance on older ships, planes and vehicles.

The latest defense budget takes a half trillion dollars out of military spending over the next decade even though Pentagon leaders expect no let up in demand for U.S. forces worldwide.

Should an unforeseen crisis arise, the consequences could be deadly.

While there is no quick or easy fix, admitting there is a problem and doing something about it should be everyone's priority.

"The aging of the inventories and equipment used by the services, the decline in the size of the Navy, escalating personnel entitlements, overhead and procurement costs, and the growing stress on the force means that a train wreck is coming in the areas of personnel, acquisition, and force structure."

Meeting the military's full modernization requirements will "require a substantial and immediate additional investment that is sustained through the long term." However, the price of U.S. weakness will be greater in the long run.

Mackenzie Eaglen is a resident fellow at AEI.