In the late 1920's a theoretical controversy within the Communist Party between Stalin's majority and Trotsky's minority revolved around the question of whether or not socialism could exist within a single country.  Stalin said it could and cited several comments by Lenin for ideological support.  Quotations from 4 separate writings are particularly noteworthy.

    1.    One of the last articles by Lenin was a pamphlet entitled On Cooperation which contains:
             “Indeed, the power of the state over all large-scale means of production, political power in the hands of the proletariat, the alliance of this proletariat with the many millions of small and very small peasants, the assured proletarian leadership of the peasantry, etc.--IS THIS NOT ALL THAT IS NECESSARY TO BUILD A COMPLETE SOCIALIST SOCIETY out of co-operatives, out of cooperatives alone, which we formerly ridiculed as huckstering and which from a certain aspect we have the right to treat as such now, under NEP?  IS THIS NOT ALL THAT IS NECESSARY TO BUILD A COMPLETE SOCIALIST SOCIETY?  IT IS STILL NOT THE BUILDING OF SOCIALIST SOCIETY, BUT IT IS ALL THAT IS NECESSARY AND SUFFICIENT FOR IT.”
         [Lenin's Collected works, Volume 33, page 468]

     2.  Additional evidence showing Lenin rejected Trotsky’s theory of Permanent Revolution is in an article entitled Slogan for a United States of Europe which states:
             “Uneven economic and political development is an absolute law of capitalism.  HENCE, THE VICTORY OF SOCIALISM IS POSSIBLE FIRST IN SEVERAL OR EVEN IN ONE CAPITALIST COUNTRY ALONE.  After expropriating the capitalists and organizing their own socialist production, the victorious proletariat of that country will arise against the rest of the world--the capitalist world--attracting to its cause the oppressed classes of other countries, stirring uprisings in those countries against the capitalists and in case of need using even armed force against the exploiting classes and their states.”
        [Lenin’s Collected Works, Volume 21, page 342 (August 23, 1915)]

    3.  Another quote from Lenin used by those disproving Trotsky's Permanent Revolution theory is:
              "Socialism if no longer a matter of the distant future, or an abstract picture, or an icon.  Our opinion of icons is the same--a very bad one.  We have brought socialism into everyday life and must here see how matters stand.  That is the task of our day, the task of our epoch....  we shall all--not in a day, but in a few years--all of us together fulfil it whatever the cost, SO THAT NEP RUSSIA WILL BECOME SOCIALIST RUSSIA."
         [Lenin’s Collected Works, Volume 33, page 443 (November 21, 1922)]

    4.  And finally, Stalin and his allies often quoted an article entitled The War Program of the Proletarian Revolution which states:
             “Thirdly, the victory of socialism in one country does not at one stroke eliminate all war in general.  On the contrary, it presupposes wars.  The development of capitalism proceeds extremely unevenly in different countries.  It cannot be otherwise under commodity production.  FROM THIS IT FOLLOWS IRREFUTABLY THAT SOCIALISM CANNOT ACHIEVE VICTORY SIMULTANEOUSLY IN ALL COUNTRIES.  IT WILL ACHIEVE VICTORY FIRST IN ONE OR SEVERAL COUNTRIES, WHILE THE OTHERS WILL FOR SOME TIME REMAIN BOURGEOIS OR PRE-BOURGEOIS.  This is bound to create not only friction, but a direct attempt on the part of the bourgeoisie of other countries to crush the socialist state’s victorious proletariat.  In such cases a war on our part would be a legitimate and just war.  It would be a war for socialism, for the liberation of other nations from the bourgeoisie.
             Engels was perfectly right when, in his letter to Kautsky of September 12, 1882 he clearly stated that IT WAS POSSIBLE FOR ALREADY VICTORIOUS SOCIALISM TO WAGE “DEFENSIVE WARS.”  What he had in mind was defence of the victorious proletariat against the bourgeoisie of other countries.
             Only after we have overthrown, finally vanquished and expropriated the bourgeoisie of the whole world, and not merely of one country, will wars become impossible.”
          [Lenin’s Collected Works, Volume 23. page 79 (written in September 1916)]

             Specifically Engels told Kautsky in this letter:
         “One thing alone is certain: the victorious proletariat can force no blessings of any kind upon any foreign nation without undermining its own victory by so doing.  Which of course by no means excludes defensive wars of various kinds....”
         These comments can only make sense if some countries have obtained socialism before others.

     A Trotskyist sent me the following quote from Lenin that supposedly supports Trotsky’s idea of permanent revolution.
      “When, three years ago, we raised the question of the tasks and the conditions of the proletarian revolution’s victory in Russia, we always stated emphatically that victory could not be permanent unless it was followed up by a proletarian revolution in the West, and that a correct appraisal of our revolution was possible only from the international point of view. For victory to be lasting, we must achieve the victory of the proletarian revolution in all, or at any rate in several, of the main capitalist countries.”
      V. I. Lenin, Our Foreign and Domestic Position and Party Tasks, Speech Delivered To The Moscow Gubernia Conference Of The R.C.P.(B.), November 21, 1920

      Anyone who tries to use this quote to prove Lenin supported Trotsky's Permanent Revolution theory is being deceptive and dishonest because he or she is failing to state what follows these comments.  The above quote used by Trots is a typical example of taking words out of context.  Here is what Lenin says afterward:
      "After three years of desperate and stubborn struggle, we can see in what respect our predictions have or have not materialized.  They have not materialized in the sense that there has been no rapid or simple solution of the problem.  None of us, of course, expected that such an unequal struggle as the one waged by Russia against the whole of the capitalist world could last for three years.  It has emerged that neither side--the Russian Soviet Republic or the capitalist world--has gained victory or suffered defeat; at the same time it has turned out that, while our forecasts did not materialize simply, rapidly and directly, they were fulfilled insofar as WE ACHIEVED THE MAIN THING--THE POSSIBILITY HAS BEEN MAINTAINED OF THE EXISTENCE OF PROLETARIAN RULE AND THE SOVIET REPUBLIC EVEN IN THE EVENT OF THE WORLD SOCIALIST REVOLUTION BEING DELAYED."
      In short, Lenin is saying:
      “We did not think the proletarian revolution could succeed without a world revolution but events in the prior 3 years have shown we were mistaken.”

      Later Lenin says:
      “Without having gained an international victory, which we consider the only sure victory, we are in a position of having won conditions enabling us to exist side by side with capitalist powers, who are now compelled to enter into trade relations with us.  IN THE COURSE OF THIS STRUGGLE WE HAVE WON THE RIGHT TO AN INDEPENDENT EXISTENCE....  WE HAVE WON THE RIGHT TO OUR FUNDAMENTAL INTERNATIONAL EXISTENCE IN THE NETWORK OF CAPITALIST STATES....  TODAY WE CAN SPEAK, NOT MERELY OF A BREATHING-SPACE, BUT OF A REAL CHANCE OF A NEW AND LENGTHY PERIOD OF DEVELOPMENT [notice he says lengthy].  Until now we have actually had no basis in the international sense.  We now have this basis,...  We see that the imperialist powers dominate the whole world although they comprise an insignificant part of the world’s population.  The fact that a country has appeared that for 3 years has resisted world imperialism has considerably changed the international situation; the minor powers--and they form the majority of the world’s population--are therefore all inclined to make peace with us.
      The entry of the socialist country into trade relations with capitalist countries is a most important factor ENSURING OUR EXISTENCE IN SUCH A COMPLEX AND ABSOLUTELY EXCEPTIONAL SITUATION.”
      Then Lenin attacked Spargo, an American social-chauvinist, who claimed the socialist system has collapsed because they were forced to enter into trade relations with the capitalist powers.  Lenin says:
      “Spargo has written that he cannot imagine better proof of the complete collapse of communism [read socialism] and the breakdown of its programme.  I think that anybody who has given thought to the matter will say the reverse.  No better proof of the Russian Soviet Republic’s material and moral victory over the capitalists of the whole world can be found than the fact that the powers that took up arms against us because of our terror and our entire system have been compelled, against their will, to enter into trade relations with us in the knowledge that by doing so they are strengthening us.  This might have been advanced as proof of the collapse of communism [read socialism] only if we had promised, with the forces of Russia alone, to transform the whole world, or had dreamed of doing so.  However, WE HAVE NEVER HARBOURED SUCH CRAZY IDEAS [Trotskyists take note] and have always said that our revolution will be victorious when it is supported by the workers of all lands [that does not mean all nations must have had socialist revolutions].  In fact, they went half-way in their support, for they weakened the hand raised against us, yet in doing so they were helping us.”
     [Lenin, COLLECTED WORKS, Progress Publishers, Moscow, 1966, Vol. 31, pages 410-414]