291. Telegram From the Embassy in Laos to the Department of State1
7638. 1. After some delay, the rainy season has begun in earnest throughout Laos. Heavy rain has been falling for the past two weeks in the Panhandle. During last several days, downpour so heavy in northern Laos as to make flying almost impossible. Mekong River Valley, which had already received nearly two feet of rainfall by this time last year, has received several inches in past few days and rice cultivation cycle has begun.
2. Result of this seasonal change, as in the past, has been dramatic reduction in level military activity throughout country. Major difference between this year and previous years is that Lao Government and friendly guerrillas hold considerable territorial advantage, which they feel fully confident to preserve. In fact, they have previously used rainy season to regain dry season losses. This rainy season they may be able convert that sort of forward activity into positive territorial gains.
3. On Ho Chi Minh and Sihanouk Trails, vehicle traffic has ground virtually to a halt. There continues to be some shuttle movement on firm, high stretches of road structure, but lowland reaches have become impassable. Our road watch teams report that in many stretches of both structures, ground has already reached saturation point and standing water has covered roads. With good luck, this condition will prevail from now until late October. It will mean that truck traffic on full length of trails will be impossible during these several months and that major use of these logistics arteries will be ruled out.
4. This does not mean that enemy use of Lao territory for logistics purpose will cease altogether during the rains. Waterways, bicycle trails, and human porters will still be used. We will shift our road watch teams and our tactics to take this into account. However, it does mean that, by and large, those enemy units in South Vietnam which depend on these two logistics routes must live on supplies already in place or in cache for the months ahead. It certainly means that they could not call up major emergency logistics over these two structures during the period ahead.
5. We do not intend to relax our road watch and other vigilance in the Panhandle, or elsewhere in Laos, during the rains. Instead, we intend to use this time to extend and improve communications, to work out better liaison and response arrangements with 7th AF, etc. but we will be [Page 584] surprised if we encounter much enemy activity in most regions and will report and evaluate what we see.
6. We will, of course, be acutely interested in any reflections, either political or military, which addresses may detect to bear out inevitable enemy acceptance of the fact that the monsoon has made its annual mark.
- Source: Department of State, Central Files, POL 27 LAOS. Secret; Limdis. Repeated to Bangkok, Hong Kong, Moscow, Saigon,CINCPAC, COMUSMACV, and 7th AF.↩