I agree, George Bush 41 is a man of immense international political experience and would be the much better choice than Bolton.

yes I agree that nuclear deterrence has played a part in avoiding great power conflicts since wwII, however the formation of the UN led to a definition of what kind of warfare is legal, which by and large the major powers have accepted. Ie. war in self-defence etc.
Prior to WWII it was quite common for states to invade and annex the territory of other states. Since the founding of the UN this is unacceptable behaviour.

The other point about nuclear deterrence is that formally the policy
that was adopted by the US evolved over a period of 20 years.
Initially Generals such as Curtis LeMay wanted to use the US superiority
with nuclear weapons to destroy the Soviet Union. In fact in an interview he boasted that he didnt need permission.

IN Erol Morris' Fog of War documentary, Robert MacNamara looks back on the Vietnam years and freely admits that they made a mistake and got involved in what was essentially a civil war. But more importantly he
states that in a 1992 meeting with Fidel Castro, he was stunned to find out that the Cubans already had some 150+ nuclear warheads.
(up to that point it was always believed that the missiles still hadnt been fitted with warheads, which is why Kennedy blockaded Cuba)

he asked Castro, ... if they had been armed, whether he would have sanctioned their use against the US. and was stunned to hear Castro's reply, that they indeed had warheads and Castro had in fact asked the Russians to use them on the US.
(as part of the deal later the US removed their missiles from Turkey)

Your third point, the rest of the world, or more notably the other economic powers such as China and INdia are indeed catching up to the US. In the end economics trumps all, and you can have the largest military but its not that useful since the US population is averse to large casualties and high taxes that come with it.

Taking on Iraqs 3rd world 5th rate army with the largest and best equipped military in the world is like beating up a baby with a baseball bat. Its another thing altogether to take on a modern military power.

At some point Americans will need to accept (like the British) that they are just another country. But if they continue along the unilateral path, (who needs the Kyoto climate treaty, or the international criminal court, or piss on the UN well do what we want)
other countries will abandon the UN and you will have the old alliances and the law of the jungle of the 19th century.

and that would be a major step back..