Who is Target of Pentagon's Proposed Preemptive N-Strikes?

Under Bill Clinton's administration, the US military doctrine does not mention the use of nuclear weapons pre-emptively or against weapons of mass destruction threats.

Now the Pentagon has revised that doctrine, as a draft for approval. It wants the option of pre-emptive strikes against a nation or terrorist group that possesses weapons of mass destruction. The revised draft also embraces other factors that justify such pre-emptive strikes, including the destruction of stockpiles of nuclear, biological or chemical weapons.

Though the draft document is officially only at the level of the Pentagon's Joint Chiefs of Staff, and not yet approved by Defence Secretary Donald Rumsfeld, we may assume that the drafting would have been given the latter's quiet nod.

The fact that the revised draft is not classified and available on the Pentagon’s website signals that it is meant to be read by “interested party” or parties.

Now who could that well be?

Hint: Last year the US Congress f**k off a proposal to examine the viability of using nuclear warhead in bunker busting bombs. Using a tactical nuclear warhead means the damage of the target will not only be earth-shattering but also prevents its reoccupation. Now, what target could that possibly be?

The revised draft has again picked up those threads that Congress killed.

Now, who did/does the US administration has in mind when it considered/considers destroying with finality certain enemy sites that may be built underground?

The revised doctrine gave the following occasions when presidential approval would be sought to press the button:

(1) Against an enemy using or intending to use weapons of mass destruction against US or allied military forces or civilians.
(2) In case of an imminent attack from adversary biological weapons that only effects from nuclear weapons can safely destroy.
(3) For attacks on adversary installations including WMD, deep, hardened bunkers containing chemical or biological weapons.

Hmmm, who is the intended culprit that the US (or someone else) fears?