Former Biden advisor explains U.S. delay in supplying ATACMS to Ukraine

He shared the information at the Harvard Kennedy School's Institute of Politics.

Sullivan emphasized that the decision was not related to the fear of a Third World War, as some had suggested. At the time, the U.S. military did not have enough ATACMS to support both itself and Ukraine.

"The reason why we didn't provide them originally is because the Secretary of Defense and the U.S. military told the president that the United States did not have enough of these in our inventory to meet our basic deterrence needs," he said.

At that time, according to Sullivan, military leaders warned President Biden against providing the systems to other countries. However, over the next two years, the U.S. produced the necessary quantity of weapons, which allowed them to transfer the missiles, including to Ukraine.

“We produced enough to be able to supply Ukraine with somewhere on the several hundred ATACMS. So that was one piece of it. The second piece of it was that in those early months in the period of April-May of 2022, the question of escalation was different than it was in 2024,” he added.

Sullivan emphasized that during this time, America learned a lot from this war and was ready to take risks.

"Part of the overall approach that we took on a range of different decisions that the president made had to do with our learning about what the level of risk tolerance was for us to be able to supply Ukraine with what it needed, while also making sure that we didn't end up in an escalatory spiral. I would just say in closing that we ended up providing Ukraine with a very significant number of these systems down to the level where, again, we basically have no more to give, and the idea that they made a major difference operationally in the war has not been borne out by the evidence. So, I think a lot has been put on this ATACMS decision to suggest, "Oh, if only you'd given it, the war would have turned out totally differently," and yet the experience of the use of it by Ukraine on the battlefield, I think, suggests that that is not, in fact, the case," he concluded.

• On March 13, the Associated Press reported that officials in Ukraine acknowledged that the Ukrainian Defense Forces had run out of American long-range ATACMS missiles.