The United States has an estimated 4,650 nuclear warheads available for delivery by more than 800 ballistic missiles and aircraft. Approximately 2,700 retired but still intact warheads await dismantlement, for a total inventory of roughly 7,400 warheads. The stockpile includes an estimated 2,130 operational warheads, about 1,150 on submarine-launched ballistic missiles and 470 on intercontinental ballistic missiles. Roughly 300 strategic warheads are located at bomber bases in the United States, and nearly 200 nonstrategic warheads are deployed in Europe. Another 2,530 warheads are in storage. To comply with New START, the United States is expected to eliminate land-based missile silos, reduce the number of launch tubes on its missile submarines, and limit its inventory of nuclear-capable bombers in coming years. Coinciding with a revised nuclear weapons strategy, the Obama administration is also planning an upgrade of all nuclear weapons systems. The three-decade-long plan would cost more than $200 billion in the first decade alone.