The event was moderated by Ambassador Susan Burk, the President’s Special Representative for Nonproliferation (but not disarmament?). The first speaker was Ellen Tauscher, the former Congresswoman from California and current Undersecretary of State for Arms Control and International Security, who had a big hand in negotiating New START. She said that the new treaty’s reduction from 2200 to 1550 nuclear warheads each for the US and Russia signified a transition from Mutual Assured Destruction to Mutual Assured Security. She pointed out that the enlargement of negative security assurances contained in the Nuclear Posture Review (NPR) did not impair US security, since the US still retained a devastating conventional capacity to respond to hostile action. Nuclear weapons (NW) would henceforth be used only in extreme circumstances (which suggests that under the old policy guidelines, NW could have been used in non-extreme circumstances). The US, she said, was ready to move on a Fissile Materials Cut off Treaty and the success of the new international NW regime would depend on three factors: irreversibility, verification and global responsibility. Everything that was being done and planned, she said, in words subsequently echoed by the other two speakers, was completely in accordance with the President’s vision of a nuclear weapons free world, but the path to this world would be ragged and uneven.

The  next speaker was Dr. Michael Nacht, Assistant Secretary of Defense for  Global Strategic Affairs, who played a large role in pulling NPR together from many corners of the administration. He took some pride in reporting that, in the interest of transparency, not only was the complete text of the new NPR, released to the public on April 6, available on line but so were the texts of the two previous ones, which until then had only been partially made  public.  Enhanced transparency, he said, also characterized the release of complete information about the numbers of US nuclear warheads, both tactical and strategic, at present and at various points in the past. Dr Nacht talked about the five elements of NPR: preventing nuclear proliferation and nuclear terrorism, reducing the role of US nuclear weapons,  maintaining strategic deterrence and stability at reduced nuclear force levels, strengthening regional deterrence and reassuring US allies and partners, and sustaining a safe, secure and effective nuclear arsenal.

The last speaker was Thomas D’Agostino, Undersecretary for Nuclear Security, U.S. Department of Energy, the man in charge of the nuclear stockpile. He presented a dazzling series of charts and statistics demonstrating how much of the stockpile is gone and how much remains.

Herewith some abbreviated highlights of the question and answer period, with this code for respondents Ellen Tauscher (ET), Michael Nacht (MN), Thomas D’Agostino (TDA) - and (DR) for when I can't remember who said this.

Q. How will the US react to the expected resolution from Egypt and other countries concerning implementation of the 1995 NPT Resolution on a nuclear weapons free Middle East?

ET: We are talking to all the governments of the region and hope for a consensus resolution.

Q. Why is the US not acting on education for disarmament and non-proliferation?

ET: We are very interested in this issue.

Q. What about withdrawal of US NW from NATO countries?

ET: The US cannot make this decision alone. It has to be the decision of all NATO countries.

Q. Why the increase in the military budget, including the new global strike weapon?

MN: We do only what is needed for security. There is no restriction on the number of global strike weapons.

Q.  Will sub-critical tests continue?

TDA: Yes.

Q. Will the US retain the full triad of NW launch platforms, ICBM, bombers and subs?

TDA: Yes, and with a shift to siteing the majority of NW on submarines, because they are the least detectable.

Q. The NPR speaks of a national research program to explore getting to a nuclear weapons free world. How will this operate?

MN: Too early to tell, NPR is only a month old. We are waiting to hear from other countries, e.g. China and Russia. In any case, it will involve a series of steps, there will be no leapfrogging to a rapid solution. Remember that the President said it might not happen in his lifetime.

Q. What is wrong with Ban-kimoon’s suggestion to start  negotiating from the model nuclear weapon convention?

ET: As Secretary Clinton said on Monday, there are many steps to be taken before we get to that point. We are willing to talk to many parties, but not in the context of a nuclear weapon convention.

Q. Why do people talk only about Israel, Iran and North Korea as violators and not about India and Pakistan?

ET: We want to see all countries brought into the non-proliferation regime.

Q. Why can’t we go down to 311 NW, as a recent report recommended?

  TDA: Taking care of a smaller number is much more difficult than taking care of a larger one.

Q. Why can’t we deter with conventional weapons?

DR: The President is keeping his promise to reduce the role of NW

Q. Why can’t we have no first use for everyone?

DR: The President believes we’re complying with our obligations under Art 6 NPT.

And don’t forget “not in our lifetime.”