Infantry body armor had at last made the transition from a dream to a reality. The M-1951 was put into production by a Philadelphia sportswear firm. And it was estimated that by the spring of 1952 nearly all Marines would be protected by the vest in combat. Saving of American lives, of course, was a primary consideration. But there was a tactical as well as humanitarian advantage to be gained. For if body armor could reduce fatal and serious wounds by as much as 50 percent, as NMFRL researchers hoped, it would mean that a large percentage of the enemy’s best antipersonnel weapons had in effect been silenced. _MAG-12 Moves to K-18_ There was no respite for 1st MAW while the 1st Marine Division remained in reserve. Operation STRANGLE was at its height, and interdiction flights called for nearly all the resources of Marine aviation during the summer of 1951. Close air support missions were made secondary. This principle was upheld by Air Force Major General Otto P. Weyland: I might suggest that all of us should keep in mind the limitations of air forces as well as their capabilities. Continuous CAS along a static front requires dispersed and sustained fire power against pinpoint targets. With conventional weapons there is no opportunity to exploit the characteristic mobility and fire power of air forces against worthwhile concentrations. In a static situation close support is an expensive substitute for artillery fire. It pays its greatest dividends when the enemy’s sustaining capability has been crippled and his logistics cut to a minimum while his forces are immobilized by interdiction and armed reconnaissance. Then decisive results can be obtained as the close-support effort is massed in coordination with determined ground action.[265] [265] Quoted in James T. Stewart, _Air Power, The Decisive Force in Korea_ (Princeton, N. J.: Van Nostrand Company, 1957), 22–23. Marine aviation officers, of course, would have challenged some of these opinions. But General Weyland insisted that in the summer and fall of 1951 “it would have been sheer folly not to have concentrated the bulk of our air effort against interdiction targets in the enemy rear areas. Otherwise, the available firepower would have been expended inefficiently against relatively invulnerable targets along the front, while the enemy was left to build up his resources to launch and sustain a general offensive.”[266] [266] _Ibid._ The UN interdiction program was costly to the Communists. Yet it remained a stubborn fact that the enemy had not only maintained but actually increased his flow of supplies in spite of bombings that might have knocked a Western army out of the war. That was because CCF and NKPA troops could operate with a minimum of 50 short tons per day per division--an average of about 10 pounds per man. It was about one-fifth of the supply requirements for an equal number of U.S. troops.