Well I don't want to go into this issue much further, particularly since I don't regard myself as a "Marxist" (I am a socialist appreciative of Marx) and because I have few ties with Trotskyists these days anyway.
But just briefly, my objection to Louis's assertion that the crisis of our time is a crisis of leadership was, that it is too general and one-sided, begging the question of how a "correct" leadership is arrived at in the first place. I don't think the question of leadership is primary, but the question of organisation. There are a lot of aspirant leaders around, it's just that they have hardly any followers. I don't think though the "crisis of leadership" slogan necessarily intensifies individualism and idealism. The issue of whether you can or cannot have "socialism in one country" turns on what you mean by socialism, what kind of socialism you aspire to. Personally, I don't regard Stalin's "socialism" as Marxian socialism, since a genuine Marxist would not implement the kinds of policies Stalin implemented. You can of course say it was a sort of socialism, but most people today would say that "if this is socialism, we don't want it". Trotsky's point was that unless the revolutionary process extends itself to other countries, shifting the balance of power further in favour of working class interests, further advances towards socialism will be hindered or blocked and the revolution will tend to degenerate under the pressure of the imperialist powers and the capitalist world market. He conceived socialism as a world society, the transition to socialism would begin in individual countries, but could be completed only in the world arena. No Trotskyist I know of would deny the need to "cooperate and at least weaken the ability of global reactionary forces to crush those revolutions". The issue is only what form that cooperation should take. Stalin wanted to build support among the "progressive bourgeoisie" for the Soviet Union, but that is a different matter. He wanted to utilise the communist parties for the defence of the Soviet Union, even at the expense of those communist parties leading revolutions in their own countries. In other words the communist parties became a bargaining tool in negotiating a detente with the imperialist powers. The theoretical basis of Marxist opposition of class alliances with the capitalist class is that such alliances do not lead to socialism and workers power, but to the watering down of workers' demands and interests, and the restabilisation of capitalism. In this sense, the Communist Manifesto mocks "bourgeois socialism": "Free trade ? For the benefit of the working class ! Protectionism ? For the benefit of the working class ! The bourgeois is bourgeois, for the benefit of the working class". That is why Louis Proyect talks about the need for clear political demarcation. You say the Marxist principle that "the emancipation of the working classes must be conquered by the working classes themselves" does not rule out political alliances with the bourgeoisie. I think it does, at least in the struggle for state power, since the bourgeoisie forms the ruling class which, precisely, has to be defeated in order to create socialism. In Marx's logic, you don't go and form alliances with your class enemy. Rather you exploit divisions within the bourgeoisie for your own political purposes, but that doesn't entail an "alliance" of these social classes. Marx' envisaged a part of the bourgeoisie breaking with their own class and joining the working class, but that is not an "alliance". This approach does not of course rule out alliances with poor peasants, working farmers, middle-class elements, unemployed and so forth. I had in mind among other things Marx's Inaugural Address. The rules of association of the First International stated that the International was established by the working men themselves and for themselves; that the emancipation of the working class had to be conquered by the working classes themselves; that in its struggle against the collective power of the possessing classes, workers could "act as a class only by constituting itself as a distinct political party, opposed to all the old parties formed by the possessing classes". Working class emancipation required both "solidarity between the manifold divisions of labour in each country" and a "fraternal bond of union between the working clases of different countries". Internationalism was essential because emancipation is "a social problem, embracing all countries in which modern society exists, and depending for its solution on the concurrence, practical and theoretical, of the most advanced countries". Because of the history of Marxism in the 20th century, I personally think the political language of Marxism has to be treated with a lot of caution. A lot of it is dogmatism, schematism, and rhetoric, which stops fresh thinking and creates ideological blinkers. That is why I don't refer to it much anymore these days. There are some Marxists who can use the language appropriately, but all that many. To tell you the truth, I have my doubts about whether Marx would have agreed with the concept of Marxism as a "system". He might have endorsed the concept of scientific socialism - Engels's book Anti-Duhring was written while he was still alive - but not Marxism.