It’s a Greek urban legend, of the type Greeks love to boost their persecution complex. On the debunking of the urban legend by language blogger Nikos Sarantakos, see:
Was it 1974? Or 1973? Or 1997? Was the issue of Turkish Daily News where it was supposedly published wiped from the archives, as Liana Kanelli claimed? Really?
And as Sarantakos said,
Βέβαια, η διάψευση θα έπρεπε να περιττεύει. Οποιοσδήποτε άνθρωπος έχει λίγο μυαλό στο κεφάλι του, καταλαβαίνει ότι είναι απολύτως αδύνατο ένας παμπόνηρος διπλωμάτης σαν τον Κίσινγκερ να ξεστομίσει τόσο ωμά λόγια! Ακόμα κι αν τα πίστευε αυτά, ποτέ δεν θα τα έλεγε –ή, αν τα έλεγε, θα τα γαρνίριζε με πολυπολιτισμικές και ανθρωπιστικές σάλτσες.
There should have been no need for a denial [by Kissinger]. Anyone with half a brain would know that it is utterly impossible that a wily diplomat like Kissinger would speak so bluntly. Even if he believed all that, he’d never give voice to it; and if he did, he’d garnish it with multicultural and humanitarian sauces.
Not to mention, as commenters on his blog pointed out, phrases like cultural roots, historical reserves, removing them as an obstacle to do strike one as being translated from Greek. (And any native speakers of English reading this, look at the question details. Does that sound like Kissinger to you?)
After some digging, it seems the ultimate source of the alleged quote is something Charles K. Tuckerman, first US ambassador to Greece, wrote in 1872.
The Greeks of to-day : Tuckerman, Charles K. (Charles Keating), 1821-1896 : Free Download & Streaming : Internet Archive
p. 145.
The principle upon which the Western powers have governed Greece since her independence of the Turkish power, has been that which Pitt declared in 1792 to be “the true doctrine of balance of power” — to wit, that the power of Russia should not be allowed to increase, nor that of Turkey to decline. After the battle of Navarino, Wellington, the demigod of Englishmen, who had pronounced that victory an “untoward event,” was for making Greece “wholly dependent upon Turkey.” This idea was supported by Lord Londonderry [Robert Stewart, Viscount Castlereagh] who wished to render Greece “as harmless as possible, and to make her people like the spiritless nations of Hindostan.” These views seem to have prevailed in effect over the liberal ideas of Palmerston, who desired to see Greece as independent of Turkey as possible.
The quotes ended up attributed to Castlereigh and Palmerston, but Sarantakos found no corroboration that Castlereigh actually made the Hindostan jibe.
Sarantakos suspects the Kissinger statement was devised by someone inspired by a conflation of Tuckerman’s observation, which had circulated in Greek translation, with something Macauley allegedly said about Hindustan (Speeches in British Parliament, 1835):
I have travelled across the length and breadth of India and I have not seen one person who is a beggar, who is a thief. Such wealth I have seen in this country, such high moral values, people of such caliber, that I do not think we would ever conquer this country, unless we break the very backbone of this nation, which is her spiritual and cultural heritage, and, therefore, I propose that we replace the old and ancient education system, her culture, because if the Indians think that all that is foreign and English is good and greater than their own, they will lose their self-esteem, their native self-culture and they will become what we want them to be, a truly dominated nation.
Mind you, Sarantakos, as a card-carrying Euro-communist, has no problem with the statement accurately reflecting US imperialist attitudes. He does have a problem with people making statements up as proof.