The principal US objective in strategic arms control is to increased stability in the US-Soviet nuclear relationship at significantly lower levels of nuclear weapons. In START, the US has achieved an equitable and effectively verifiable agreement that reduces the number of strategic nuclear delivery vehicles and the warheads on them. Furthermore, limits in START are designed specifically to constrain the most destabilizing weapons of the Soviet arsenal--heavy ICBMs--while encouraging greater reliance on slower, stabilizing delivery systems, e.g., heavy bomber aircraft.
| The Central Limits of START | |
|---|---|
| Strategic Nuclear Delivery Vehicles (SNDVs) Deployed ICBMs and their launchers Deployed SLBMs and their Launchers Deployed Heavy Bombers | 1600 |
| Accountable Warheads: | 6000 |
| Total Warheads deployed on ICBMs and SLBMs: | 4900 |
| Warheads on Mobile ICBMs: | 1100 |
| Warheads on 154 Heavy ICBMs: | 1540 |
| Heavy Bombers equipped for long range nuclear ALCMS (LRNA): | US - 10 warheads attributed to the first 150 bombers. Each additional bomber is attributed with a warhead count equal to the number of LRNA for which it is equipped. No LRNA heavy bombers will be equipped with more than 20 ALCMs. USSR - 8 warheads attributed to the first 180 bombers. Each additonal bomber is attributed with a warhead count equal to the number for which it is equipped. No LRNA heavy bomber will be equipped with more than 16 LRNA. |
| Heavy Bomber Aircraft equipped nuclear weapons other than LRNA: | 1 warhead per bomber |
| Throw-weight: | The throw-weight ceiling, the aggregate weight of the payload of ICBMs and SLBMs, has been set at 3600 metric tons. |
| Timetable for Reductions: | Seven years in three phases, with equal levels at the end of each phase. |
| Duration of Agreement: | Fifteen years unless superseded earlier, with an option to extend for five years increments if both sides agree. |