” …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”. ”
V. I. Lenin (1917)
Source: V. I. Lenin, Collected Works (Vol 23), Progress Publishers, Moscow, 1964
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