In laying out a case for Patriot (“What the Patriot Missile Deployment to Turkey Tells Us About Future Weapons Procurement in an Age of Austerity,” Roll Call, Feb. 21), John Hulsman failed to consider the Army’s now-urgent air and missile defense requirements. A war is being waged over the Army’s future relevance in AMD as U.S. defense strategy rebalances toward potential conflicts in Asia. Without existing bases, U.S. forces must become more agile and expeditionary, as will the weapon systems they employ.

At the AUSA Winter Symposium in February, Major General Thomas Spoehr, the Army’s director of program analysis and evaluation, noted that the Army’s current weapon systems are essentially the same systems it used to fight in Iraq and Afghanistan. Now, the Army does not have a new fleet of equipment to sustain it over the long haul or for new missions.

The 40-year-old Patriot air and missile defense system is just such a system. Designed during the Cold War and in the field for 30 years, the venerable system reflects defensive needs of the era that has passed. It is adequate for the current NATO mission to defend Turkey because the ballistic missile threat is well defined and located in front of Patriot’s sectored radars and directional launchers. The Turkish scenario also provided the luxury of time, allowing two months for two Patriot batteries to be shipped by sea before becoming operational. This gift of time is not likely in future conflict scenarios that include the realities of crisis deployment, forced entry, airlift constraints, an evolving asymmetric cruise missile threat, and Americans in harm’s way.

The recently published Army 2012 Air and Missile Defense Strategy describes the capabilities our forces must have now, not 25 years from now. The air and missile defense force must be agile, capable, affordable and flexible enough to execute operations as part of joint and coalition forces.

Needed capabilities include a networked open architecture and 360-degree surveillance and fire control. These are features that Patriot does not have today and will likely never have despite continuing investment and years of development. I remain perplexed why our nation would not instead reap the benefits of the Medium Extended Air Defense System, whose capabilities and cost of operation are exactly what is called for in the 2012 AMD Strategy.

Ten years ago, Army leadership published a report listing shortcomings of the Patriot system after the conflict in Iraq. The heavy system took six months to fully deploy in numerous naval shipments. It could not be easily repositioned when ground forces moved.

The sectored system could not defend against non-ballistic threats outside of its narrowly defined search sectors. Despite billions of dollars spent to improve Patriot in the past decade, the Army still doesn’t have a system that meets the requirements it defined after the Iraq War.

The technological shortcomings defined after the Iraq War exist today but have been successfully answered in an unprecedented intercept test at White Sands Missile Range in the fall of 2012. The 360-degree MEADS system destroyed an air-breathing threat attacking the tactical site from behind — an impossible feat with the Patriot Missile System.

MEADS meets the Army’s AMD Strategy requirements and provides the advanced capabilities our forces so desperately need. Each MEADS element is lightweight and truck-mounted. Its rotating radars provide 360-degree capability, and all components are designed to be networked using open architecture software and with plug-and-fight capability — exactly the characteristics all future systems must possess. A MEADS battery provides eight times the defensive coverage of a Patriot battery and slashes airlift requirements so the U.S. can get to the fight. MEADS does more with fewer vehicles and fewer personnel — and can generate enough manpower savings to pay for itself.

Our Army faced the same kind of decision in 1973 when critics argued that Red Eye and Chaparral were good enough. Those same critics argued that these systems were widely adopted by our allies and therefore we should stay with the old technology. But the threat changed and modern warfare changed — Patriot was needed. Now the threat and the global environment our Army must fight in have changed. We do not have the luxury of time to modify an existing system whose valiant service no one would argue with. The capabilities required for a modern Air and Missile Defense are clearly defined in the AMD Strategy.

Our nation and our partner allies have invested billions in scarce resources to accomplish what many said could not be done: protection against tactical ballistic missiles, cruise missiles and other stressing air-breathing threats attacking from any direction. We can do no less for our men and women in uniform than to complete the MEADS Design and Development contract and move forward. Harvesting mature, network-capable MEADS assets is the quickest and most cost-effective way for the U.S. Army to achieve its integrated air and missile defense strategy.

Retired Army Lt. Gen. Dennis D. Cavin, former commanding general of the U.S. Army Air Defense Center at Fort Bliss, Texas, and a former Lockheed Martin executive