Dear Mr. President:
This will acknowledge your letter of December 20, 1972.
There is nothing substantial that I can add to my many previous messages, including my December 17 letter, which clearly stated my opinions and intentions. With respect to the question of North Vietnamese troops, we will again present your views to the Communists as we have done vigorously at every ether opportunity in the negotiations. The result is certain to be once more the rejection of our position. We have explained to you repeatedly why we believe the problem of North Vietnamese troops is manageable under the agreement, and I see no reason to repeat all the arguments.
We will proceed next week in Paris along the lines that General Haig explained to you. Accordingly, if the North Vietnamese meet our concerns on the two outstanding substantive issues in the agreement, concerning the DMZ and type method of signing and if we can arrange acceptable supervisory machinery, we will proceed to conclude the settlement. The gravest consequence would then ensue if your government chose to reject the agreement and split off from the United States. As I said in my December 17 letter, “I am convinced that your refusal to join us would be an invitation to disaster-to the loss of all that we together have fought for over the past decade. It would be inexcusable above all because we will have lost a just and honorable alternative.”
As we enter this new round of talks, I hope that our countries will now show a united front. It is imperative for our common objectives that your government take no further actions that complicate our task and would make more difficult the acceptance of the settlement by all parties. We will keep you informed of the negotiations in Paris through daily briefings of Ambassador [Pham Dang] Lam.
I can only repeat what I have so often said: The best guarantee for the survival of South Vietnam is the unity of our two countries which would be gravely jeopardized if you persist in your present course. The actions of our Congress since its return have clearly borne out the many warnings we have made.
Should you decide, as I trust you will, to go with us, you have my assurance of continued assistance in the post-settlement period and that we will respond with full force should the settlement be violated by North Vietnam. So once more I conclude with an appeal to you to close ranks with us.