China is the only one of the five original nuclear weapon states that is quantitatively increasing the size of its nuclear arsenal and it now is estimated to have approximately 260 warheads. The arsenal’s capabilities are also increasing as older missiles are replaced with newer ones. As China assigns a growing portion of its warheads to long-range missiles, the US intelligence community predicts that by the mid-2020s the number of warheads on missiles capable of threatening the United States could increase to well over 100. The nuclear warheads in the Chinese stockpile are intended for delivery mainly by land-based ballistic missile but also by aircraft and submarines. The current force has nearly 150 nuclear-capable land-based missiles, half of which are short-range and medium-range. China has also built two types of submarine-launched ballistic missiles, one developed for a submarine no longer considered operational and the other in the final stages of development.