Karl Kautsky in this important article of 1907 answers the authors of a draft resolution introduced to the International Socialist Congress in Stuttgart that stated "congress does not in principle reject all colonial policy for all time, as it could have a civilizing effect under a socialist regime."
Following Marx and Engels, Kautsky defended the orthodox social-democratic line of unconditional opposition to colonialism:
[...] the end of the present-day capitalist colonial policy will mean the end of all colonial policy. The victory of the proletariat will of course find the most various kinds of cultural stages in existence in the world, and this victory will not make the spread of European technology, of European science and thought amongst the peoples of the tropics unnecessary
The proletariat cannot free itself without freeing the whole of mankind. In this lies its greatness, its power of attraction, because of which its struggle for emancipation, its class struggle, has from the beginning drawn to it the greatest and most far-seeing spirits of all classes. This is the sign under which we will be victorious.