"American airmen not only underestimated the North Vietnamese defenses, they especially underestimated the impact of flak". Kenneth P. Werrell, Linebacker II: The Decisive Use of Air Power?Lưu trữ 2007-11-24 tại Wayback Machine, Air University Review, January-March 1987
Clashes: Air Combat Over North Vietnam, 1965-1972, Marshall L. Michell III, Naval Institute Press, ISBN/SKU: 9781591145196, page 271, trích "Linebacker II was completely different from the interdiction policy of Rolling Thunder and Linerbacker I; Linerbacker II would be a sustained maximum effort to destroy all major target complexes in the Hanoi and Haiphong areas. This could be done by Phantoms, even with LGBs; it required a massive application of force, which could only be exerted by B-52 strikes. Linebacker II also involved the removal of many of the restrictions surrounding the previous operations over North Vietnam, except an atempt to "minimize the danger to civillian population to the extent feasible without compromising effectiveness" and to "avoid known POW compounds, hospitals and religious structures."
Nguyễn Thị Tâm Bắc, Hà Nội máu và hoa, báo Quân đội Nhân dân, 22/12/2007
"American airmen not only underestimated the North Vietnamese defenses, they especially underestimated the impact of flak". Kenneth P. Werrell, Linebacker II: The Decisive Use of Air Power?Lưu trữ 2007-11-24 tại Wayback Machine, Air University Review, January-March 1987
