WE ALL THINK OF THEM AS SCOTS:

It comes down to this: Scots are bound more tightly to each other -- by history, culture and ethnicity -- than they are to the rest of the U.K. In this sense, Scotland is, and for centuries has been, another country. Its desire for full nationhood has waxed and waned, but it certainly isn't new. The union is hundreds of years old, but the things that make Scotland different haven't been smoothed away, which tells you something.

What has changed in recent decades is that the U.K. has become both less hospitable to the Scots and less necessary.

The U.K. is centralized to an unusual degree, and ever more so. London and its surroundings continue to increase their cultural and economic dominance, and the Scots are right to feel marginalized. Seeming to push against this was the devolution of government, notably through the Scotland Act of 1998, which set up a Scottish parliament with limited powers. This was a mostly sincere effort to meet the Scottish demand for self-rule, but in a subtle way, it served to underline the disparity in status.

Devolution grafted special arrangements for Scotland onto an essentially unchanged settlement in England -- even at the cost of glaring constitutional anomalies (Scottish members of the Westminster parliament continued to vote on English matters; English members of Parliament don't vote in Scotland). You might think this was a nice deal for Scotland -- and it was generous enough, at any rate, to cause resentment in England. But there's another way of reading it (you have to imagine it in an English accent): "You can have more self-rule, but only if it has no implications for us. That's how little you matter."

More devolution of this kind is again on offer if Scotland votes against independence. Depending on the details, it would go some way toward meeting the Scottish desire for self-government, but it won't meet the Scottish demand to be respected as a nation. Moreover, to the extent that Scotland makes a success of its devolved political powers, it would demonstrate that it can, in fact, rule itself. Devolution was supposed to satisfy the appetite for self-determination; in fact, it made Scotland hungry for more.

The world has changed, too. Scots made a conspicuously disproportionate contribution to the running of the British empire. In the wars of the 20th century, they were full partners with the rest of the U.K. in fighting for Britain and celebrated as such. That unifying sense of grand British purpose, defined by colonial prerogatives and obligations, as well as by existential threats (first Germany, then Germany again, then the Soviet Union), has gone.

The world is by no means a safe place, but -- Russian President Vladimir Putin and Islamic State notwithstanding -- it's safer than before. Today the European Union offers small nations equal standing in a peaceful new regional order, with guaranteed access to each other's markets and a promise of mutual support. Small EU countries, even those on Russia's borders, feel no need to be absorbed by a condescending protector. If Ireland can succeed as a modern European nation and never regret its independence, why not Scotland?

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