One could argue that there would have been far MORE dead commies and Taliban, had we had a more dependable and effective weapon/caliber. We had requests from the field during the hardest part of the Iraq War for M-14s because the M-16s weren't doing the job adequately - particularly at extended ranges. I was able to locate 2,500 Condition Code A M-14s at Albany GA and the magazines and the gauges and finally the M-80 ball ammo in stripper clips - but some pipsqueak major at HQMC stopped everything because they "didn't want to interefere with the Designated Marksmanship Rifle acquisition".
It wasn't "my daddy's M16": I was issued one of those damn things in Vietnam and it jammed like no tomorrow and it didn't kill people well enough. I got my M-14 back and kept it for the rest of my time in country.
The new ones shoot better and the new bullet design is better but we need a better battle weapon to replace it - something that isn't a "least bidder" product.