>>507647919
There are currently at least 6 B-2 Spirit stealth bombers stationed at Diego Garcia air base in the Indian ocean, along with several B-52 heavy bombers.
Each B-2 can carry up to 16 B83 nuclear bombs.
Each B83 has a yield of 1.2 megatonnes of TNT.
This would be over 115 megatons of nuclear yield in a single, completely undetected sortie of B-2s.
Tehran is approximately 3300 miles from Diego Garcia. Tehran, along with every other part of Iran is well within the B-2's ~6000 mile unrefueled range.
The atomic bombs dropped on Hiroshima and Nagasaki were estimated to have yields of 15-20 kilotons.
This all means that the US can drop the equivalent of almost 8000 Hiroshimas anywhere in Iran, at any time, completely undetected and the Iranians would have no idea it is coming until they see the first flash.
The B-2s may already be on their way.