It would be easy enough for a George Soros type to stimulate the same here. As much as I love the country the Founding Fathers created, it appears to be gone. So, even I would be partial to the idea of re-starting a limited government, private property type country.
I believe the Scottish are socialists.
1. The Special Relationship will be undercut. The United Kingdom is far and away America’s biggest and most important ally. Not necessarily. Japan is America's biggest trading partner outside North America. They may not contribute a lot of men and military equipment to Allied efforts, but they contribute the most money. By far.
2. Britain’s nuclear deterrent will have to be moved.
Not necessarily. Once Scotland comes to their senses, it is obvious that the will owe England a lot of money for the break-up. There is no less painless way to pay some of it back than by leasing bases.
3. The coalition against Isil will be weakened
See item #2. The UK contribution to the alliance is about 5% of the men and material. The Scottish contribution to the UK is maybe 8% or 9%, IOW not even 1% of the total men and material. And that assumes that Scotland will go full neutral.
4. US markets will take a hit.
Maybe, short-term. Long-term, really how important is Scotland to world markets? Maybe as important as the Republic of Ireland? However, more important than Wales or Portugal.
5. An independent Scotland will be an insignificant ally to the U.S.
And it is a significant ally now? See item #3.
FWIW, I am not cheering for a separation from the United Kingdom. I hope it fails, if only because Scotland is likely to be a basket case only slightly less than a Greece or a Portugal.
But if it passes, the sky will not have fallen any more than the separation of the Irish Republic from the UK in the previous century.