Newly declassified documents illuminate the nuclear collaboration between Washington and Paris—and reinforce that the US-India nuclear deal is a very different type of partnership.
In late May, the Washington, DC-based Woodrow Wilson International Center for Scholars published an important dossier entitled “US Secret Assistance to the French Nuclear Program, 1969-1975: From ‘Fourth Country’ to Strategic Partner,” with scholar William Burr of the National Security Archive providing a contextual analysis of more than fifty recently declassified documents.
That the United States and France cooperated on nuclear matters has been publicly known for more than twenty years; historians such as Richard H. Ullman and Marc Trachtenberg on the American side have done very good research into it. What might perhaps be more surprising for some US readers is that there has been much work done on the subject in France in the last two decades, including by serious historians such as Pierre Melandri, Vincent Nouzille, Georges-Henri Soutou, and Maurice Vaïsse. For years it has been a matter of public record that Washington and Paris had cooperated on ballistic missiles, and that Washington had helped, in particular, with the development of modern re-entry vehicles (multiple warheads, hardening, etc.). The United States is also believed to have given information to France about the capabilities of the antiballistic missile defense system surrounding Moscow. The existence of some US-French cooperation on nuclear weapons themselves, notably on safety, is also well known.
But the recently declassified US documents presented by Burr shed new light and provide many new details on the complex nature of the relationship between the two countries. The documents in the dossier pinpoint 1970 as the turning point at which President Richard M. Nixon made a strategic decision to help France. The documents also confirm, on the US side, the procedure known as “negative guidance” (a technique mentioned in 1991 in former President Valéry Giscard d’Estaing’s memoirs) that was used by Washington in its cooperation with France to avoid contravening US law. The documents suggest that the United Kingdom was kept apprised of the US-French cooperation despite an apparent promise to the contrary made to Paris. And they reveal that the transition from atmospheric testing to underground testing had been a key topic of conversation between the two countries.
As is well known, Washington initially opposed the nascent independent French nuclear force as proposed by Charles de Gaulle when he returned to power in 1958. In particular, the John F. Kennedy and Lyndon Johnson administrations feared that further nuclear proliferation would increase the risk of the United States becoming embroiled in a nuclear war. After the French nuclear force became a reality anyway, the Nixon administration made the wise decision that, since it could not stop the French program, Washington might as well take a stake in it. The idea was to reinforce the Western deterrent against the Soviet Union, while ensuring that the United States would know more about French nuclear forces than it would have otherwise, and, more broadly, to ensure that France stayed firmly anchored in the Western camp. For its part, Paris badly wanted to “save the time and money it would take to work out the problems [with ballistic missiles] on their own” (as one US official put it in one of the declassified documents) in order to build a credible deterrent as fast as possible.
The reason why the scope and depth of US-French nuclear cooperation stayed secret for so long is that both countries were, in a sense, stretching the limits of their respective national strategic paradigms or narratives: nuclear nonproliferation for the United States, and nuclear independence for France. An additional reason for the secrecy is that, regarding the strictly nuclear part of the relationship, Washington may have, on some issues, violated the spirit—if not at times the letter—of US domestic law (e.g., the Atomic Energy Act).
However, US-French nuclear cooperation did not really amount to secretly running a policy that was the opposite of the public stance taken by both governments. France was already a nuclear power, acknowledged as such by the Treaty on the Non-Proliferation of Nuclear Weapons (NPT), and—after de Gaulle’s departure from power in 1969—had a fairly good relationship with the United States. In 1974, the North Atlantic Treaty Organization (NATO) recognized the French deterrent’s contribution to the security of the Atlantic Alliance, and there were discreet consultations with NATO about the conditions under which a war in Europe could become nuclear. From what is publicly known, Washington never provided a warhead design or anything of the sort that France would not have been able to develop on its own. And what is known about US-French cooperation does not change the fact that Paris remained more independent from a technical, industrial, and operational point of view than London ever was.
The Burr dossier may give the impression to uninformed readers that US-French nuclear cooperation was a one-way street. It was—and is—not. However, whereas the missile cooperation was always, it seems, unilateral, the nuclear cooperation evolved into much more of a two-way street, with most of this cooperation developing long after 1975. In particular, a bilateral agreement signed in 1985 broadened the scope of bilateral exchanges in the nuclear domain (and put that cooperation in conformity with US domestic law). This agreement was updated in 1996, as both countries were beginning to adapt to the ban on nuclear testing. (Details on this phase will be publicly available only in the future.)
Apart from the United Kingdom, France seems to be the only country that could have received the kind of assistance that Washington provided: it was and remains the only other formal nuclear ally of the United States, and a legitimate possessor of nuclear weapons in the sense of the NPT (even though it was not a party to that agreement in the 1970s).
The US-French nuclear cooperation will likely put some readers in mind of another key nuclear country that takes pride in its independence: India. Is the nuclear partnership signed between New Delhi and Washington in 2005 in any way comparable to US-French nuclear cooperation? The answer is no. There is no reasonable comparison between the two situations. India remains outside of the NPT and is not a formal US ally, and there is no reason to believe that the two countries could collaborate on the same kind of sensitive nuclear programs.
At the same time, it would not be inappropriate to suggest that, as in the case of France, the United States is using nuclear cooperation with New Delhi to stay close to India’s progress; even though Washington did not approve of India’s initial choice to pursue the bomb, today it is the rational choice to help it, rather than to fight it.
 Strictly speaking, the 1985 agreement was an amendment to an existing agreement that was signed by the two countries in 1961, when France was still part of the NATO integrated military structure.