Treaty obligations limit the count of American nuclear weapons before costs do. Minuteman III ICBMs are technically capable of carrying multiple independent ree

Treaty obligations limit the count of American nuclear weapons before costs do. Minuteman III ICBMs are technically capable of carrying multiple independent reentry vehicles but treaty compliance means that they all carry one warhead in practice. Trident II SLBMs are still deployed in MIRV'd configurations -- though with fewer warheads than they are technically capable of -- so in practice there are more warheads deliverable by the American submarine fleet than by its land based ICBMs. Of the 280 submarine launch tubes, only 212 were counted as deployed with as many Trident II missiles loaded. The treaty counts a missile as deployed if it is in a launch tube regardless of whether the submarine is deployed at sea. The United States has declared that it will not deploy more than 240 missiles at any time. Assuming each deployed submarine carries a full missile load, the 212 deployed missiles correspond to 10 submarines fully loaded with a total of 200 missiles. The remaining 12 deployed missiles were onboard one or two submarines loading or offloading missiles at the time the count was made. The data shows that the 212 deployed missiles carried a total of 945 warheads, or an average of 4 to 5 warheads per missile, corresponding to 70 percent of the 1,344 deployed warheads as of September 1, 2017. The New START data shows the United States now has just under 400 Minuteman III ICBMs in silos, down from 405 in March 2017. Normally the Air Force strides to have 400 deployed but one missile was undergoing maintenance. Although the number of deployed ICBMs had declined from 450 to 400, the total numbers of missiles and silos have not. The data shows the Air Force has the same number of missiles and silos as in March 2017 because 50 empty silos are “kept warm” and ready to load 50 non-deployed missiles if necessary. Reduction of deployed ICBMs started in 2016, five years after the New START was signed. And the actual ICBM force is the same size as when the treaty was signed. The 399 deployed ICBMs carried 399 W78/Mk12A or W87/Mk21 warheads. Although normally loaded with only one warhead each, the Trump NPR confirms that “a portion of the ICBM force can be uploaded” if necessary. We estimate the ICBM force has the capacity to carry a maximum of 800 warheads. "New Data Shows Detail About Final Phase of US New START Treaty Reductions" https://fas.org/blogs/security/2018/01/new-start-full-data/ https://fas.org/blogs/security/2018/01/new-start-full-data/