is that the North Vietnamese have retained the same
 capacity they had last year to move at least 400 tons of
 supplies a day to the end of the motorable routes along
 the border of South Vietnam.
 8. It is difficult to predict the extent of which
 the interdiction program proposed under Alternative I could
 reduce the capacity of the road system in Route Packages I,
 II, and III. A case study of US bombing in North Vietnam
 indicates that the maximum reduction achieved in bombing
 roads was about 25 percent. Even if a more intensive program
 were to double this rate of interdiction, the capacity
 remaining on the two major routes into Laos--15 and 137--would
 still be at least five times greater than that required
 to move supplies at the 1966-1967 dry season rates.
 9. The major effect of the program outlined in Alternative
 I would be to increase the requirements for ??power and
 vehicles needed to sustain the movement of supplies. We
 estimate that an intensified interdiction progra would raise
 the manpower requirement by about 20,000-25,000 persons.
 This would be a 30-percent addition to the manp??
 to maintain logistic routes in Military Region IV and in Laos.
 The added burden could be met easily. North Vietnam has an
 estimated 220,000 full-time and 100,000 to ??,000 part-time
 -5-
 
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