Puerto Rico has the option of independence whenever it wants -- and so far it hasn't wanted. Probably because it's not very wealthy, and Puerto Ricans enjoy full US citizenship and can come and go on the mainland as they please, if they want better opportunities. It's kind of a win-win situation for them.
It's our only dominion or protectorate, but we actually own a whole bunch of islands around the globe, from American Samoa to the US Virgin Islands. They are usually territories rather than protectorates.
<<In fact, quite a sizeable number of Brits genuinely believe that the USA only refers to, or purports to believe in, a "special kinship" or a "bond of blood brotherhood" with Great Britain when it is to their advantage and/or when they want something in return from the British. >>
Well, yeah .... what else are relatives for?
To be honest, the term (and concept) "special relationship" was coined by Winston Churchill and remains far stronger in the British psyche than in the American. And it was really about what the *UK* could get out of the deal; namely, a powerful alliance to keep it safe, further its ideals and civilization, and maintain the preeminence of what was a battered British Empire sort of by proxy.
In his famous 1946 speech "The Sinews of Peace", he speaks of various special relationships as being the foundation for the UN and the safeguarding of the new peace that had finally come after years of war. He felt that the natural alliances between the US and Canada, Canada and the UK, and the US and the UK made for a firm foundation of at least three large and/or influential nations who could act as watchdogs. He also invoked the long-standing special relationship between Portugal and Great Britain and those between the US and Latin America.
"Neither the sure prevention of war, nor the continuous rise of world organization will be gained without what I have called the fraternal association of the English-speaking peoples. This means a special relationship between the British Commonwealth and Empire and the United States. This is no time for generalities, and I will venture to be precise. Fraternal association requires not only the growing friendship and mutual understanding between our two vast but kindred systems of society, but the continuance of the intimate relationship between our military advisers, leading to common study of potential dangers, the similarity of weapons and manuals of instructions, and to the interchange of officers and cadets at technical colleges."
He goes on to offer his vision of how such a large-scale tribal alliance (which is essentially what it is) could enforce the principles of the infant UN:
"I spoke earlier of the Temple of Peace. Workmen from all countries must build that temple. If two of the workmen know each other particularly well and are old friends, if their families are inter-mingled, and if they have "faith in each other's purpose, hope in each other's future and charity towards each other's shortcomings" - to quote some good words I read here the other day - why cannot they work together at the common task as friends and partners? Why cannot they share their tools and thus increase each other's working powers? Indeed they must do so or else the temple may not be built, or, being built, it may collapse, and we shall all be proved again unteachable and have to go and try to learn again for a third time in a school of war, incomparably more rigorous than that from which we have just been released."
Having said that, he extends the embrace of a new special relationship to the rest of Europe, in a quest for a unified Europe, now realized as the modern day EU:
"The safety of the world requires a new unity in Europe, from which no nation should be permanently outcast. It is from the quarrels of the strong parent races in Europe that the world wars we have witnessed, or which occurred in former times, have sprung. Twice in our own lifetime we have seen the United States, against their wishes and their traditions, against arguments, the force of which it is impossible not to comprehend, drawn by irresistible forces, into these wars in time to secure the victory of the good cause, but only after frightful slaughter and devastation had occurred. Twice the United States has had to send several millions of its young men across the Atlantic to find the war; but now war can find any nation, wherever it may dwell between dusk and dawn. Surely we should work with conscious purpose for a grand pacification of Europe, within the structure of the United Nations and in accordance with its Charter. That I feel is an open cause of policy of very great importance ."
And he then goes on in the very next paragraph to coin an even more famous phrase: the Iron Curtain.
"In front of the iron curtain which lies across Europe are other causes for anxiety. In Italy the Communist Party is seriously hampered by having to support the Communist-trained Marshal Tito's claims to former Italian territory at the head of the Adriatic. Nevertheless the future of Italy hangs in the balance. Again one cannot imagine a regenerated Europe without a strong France. All my public life I have worked for a strong France and I never lost faith in her destiny, even in the darkest hours. I will not lose faith now. However, in a great number of countries, far from the Russian frontiers and throughout the world, Communist fifth columns are established and work in complete unity and absolute obedience to the directions they receive from the Communist center. Except in the British Commonwealth and in the United States where Communism is in its infancy, the Communist parties or fifth columns constitute a growing challenge and peril to Christian civilization."
He wraps it all up with a reiteration of the special relationship and its potential implications for the future security of the UK, the UN, and the growing communist threat:
"Let no man underrate the abiding power of the British Empire and Commonwealth. Because you see the 46 millions in our island harassed about their food supply, of which they only grow one half, even in war-time, or because we have difficulty in restarting our industries and export trade after six years of passionate war effort, do not suppose that we shall not come through these dark years of privation as we have come through the glorious years of agony, or that half a century from now, you will not see 70 or 80 millions of Britons spread about the world and united in defense of our traditions, our way of life, and of the world causes which you and we espouse. If the population of the English-speaking Commonwealths be added to that of the United States with all that such co-operation implies in the air, on the sea, all over the globe and in science and in industry, and in moral force, there will be no quivering, precarious balance of power to offer its temptation to ambition or adventure. On the contrary, there will be an overwhelming assurance of security."
There's a nice pinch of shameless pandering to the US -- this speech was, after all, given to an audience of American university students at Westminster College in Missouri:
"The United States stands at this time at the pinnacle of world power. It is a solemn moment for the American Democracy. For with primacy in power is also joined an awe-inspiring accountability to the future. If you look around you, you must feel not only the sense of duty done but also you must feel anxiety lest you fall below the level of achievement. Opportunity is here now, clear and shining for both our countries. To reject it or ignore it or fritter it away will bring upon us all the long reproaches of the after-time. It is necessary that constancy of mind, persistency of purpose, and the grand simplicity of decision shall guide and rule the conduct of the English-speaking peoples in peace as they did in war. We must, and I believe we shall, prove ourselves equal to this severe requirement."
Followed by:
"It would nevertheless be wrong and imprudent to entrust the secret knowledge or experience of the atomic bomb, which the United States, Great Britain, and Canada now share, to the world organization, while it is still in its infancy. It would be criminal madness to cast it adrift in this still agitated and un-united world. No one in any country has slept less well in their beds because this knowledge and the method and the raw materials to apply it, are at present largely retained in American hands. I do not believe we should all have slept so soundly had the positions been reversed and if some Communist or neo-Fascist State monopolized for the time being these dread agencies."
And by:
"It is not our duty at this time when difficulties are so numerous to interfere forcibly in the internal affairs of countries which we have not conquered in war. But we must never cease to proclaim in fearless tones the great principles of freedom and the rights of man which are the joint inheritance of the English-speaking world and which through Magna Carta, the Bill of Rights, the Habeas Corpus, trial by jury, and the English common law find their most famous expression in the American Declaration of Independence."
He even goes so far as to allow for the possibility of a common citizenship --now enjoyed, of course, not by the culturally allied but far-flung members of the Anglosphere but by the geographically allied but culturally diverse members of the European Union:
"The United States has already a Permanent Defense Agreement with the Dominion of Canada, which is so devotedly attached to the British Commonwealth and Empire. This Agreement is more effective than many of those which have often been made under formal alliances. This principle should be extended to all British Commonwealths with full reciprocity. Thus, whatever happens, and thus only, shall we be secure ourselves and able to work together for the high and simple causes that are dear to us and bode no ill to any. Eventually there may come - I feel eventually there will come - the principle of common citizenship, but that we may be content to leave to destiny, whose outstretched arm many of us can already clearly see."
http://www.nato.int/docu/speech/1946/S460305a_e.htm