<p>The bombers went out every day until the Christmas one-day standdown. Eleven B-52s had been lost by then, six on a single black day, 20 December. When Linebacker II began again the day after Christmas, the 24-hour lull had been used to good effect, and a large and strong force took off.
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<p>The NVA missile inventory had been estimated at a total of about 1,000, and about 100 were being fired each day at the attacking fleets. At that rate, the defenders could be expected to run out of missiles in about 10 days, assuming that interdiction was keeping them from getting any more to the SAM sites. Apparently it did, because for the last two days the B-52s cruised over the targets and were not once struck by enemy fire.
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<p>Damage assessment to the targets was done by reference to low-level reconnaissance photography done by Strategic Air Command's drones. They operated below the cloud cover and, being small and speedy, were very difficult to detect and bring down. Their photos were processed in Southeast Asia and rushed to the Joint Chiefs in Washington by a special daily KC-135 courier flight. Within 24 hours after the pictures had been printed from the negatives, they were being used for target damage assessment and planning the next strikes.
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<p>Civilian casualties were very low, in spite of the potential for mass killings. By North Vietnamese estimates, between 1,300 and 1,600 civilians were killed, a remarkably low figure and one that, given the source, is more likely to be larger than smaller than the actual number.
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<p>The attack force, including SAC's B-52s, destroyed or damaged more than 1,600 military structures, and 373 pieces of railroad rolling stock. About 3 million US gal (11 million liters) of POL stores had been torched or blown into vapor. More than 500 line cuts slowed rail traffic from a torrent to a trickle, and 10 airfields were hit.
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<p>The B-52s flew 729 sorties, the tactical aircraft about 1,000. Fifteen B-52s were lost, and 11 tactical aircraft. The North Vietnamese lost eight planes, two of them to B-52 tail gunners.
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<p>The results of Linebacker II never have officially been linked to the almost immediate resumption of the peace negotiations, but it is impossible to accept that the air campaign did not have that final effect. Whether or not the administration wanted to admit it, the pounding that the North took during those 11 days had to be a factor in their decision to go back to negotiations in Paris.
