You're asking really great questions comrade. Proud of you.
Borders are an interesting one where it's not exactly a settled matter within leftist movements. Anarchists, or at least anyone deserving of being called one, are going to be against the concept of borders entirely. Governments or other oppressive bodies would be necessary for constructing/"defending" borders, so that's right out under anarchist ideologies. Different flavors of Marxists on the other hand have different ideas, but "workers of the world unite!" wasn't written by Marx in the Manifesto for nothing. National borders and national identity more broadly is seen as a reactionary concept that promotes an idealist conception of people over a class conception. Workers in different countries have far more in common with each other than the bourgeoisie from their own countries. A communist ideal society is stateless, classless, and moneyless (meaning money representating financial capital is not a standard of exchange). I'd say that leftists in general agree with that as a goal, but anarchists would not support using a "state" as a vehicle for reaching it. "Marxists" on the other hand (using Marxist loosely here, there are anarchist Marxists) would probably be okay with a socialist state existing to build towards that goal, and with a state tends to come state like things such as borders. That doesn't mean they'd enforce them or even draw them the same way as we do today, but it doesn't rule them out ideologically speaking. One of the central ideas of Marxist-Leninism is that workers must seize the power of the state in order to oppress the bourgeoisie (as opposed to the current arrangement where the bourgeois state oppresses the working class of course). Once their institutions have been thoroughly deconstructed Marxist-Leninists believe the state both can and should be phased out over time. Anarchists are either skeptical of this transition actually taking place or ideologically opposed to even a temporary state.
You're asking really great questions comrade. Proud of you.
Borders are an interesting one where it's not exactly a settled matter within leftist movements. Anarchists, or at least anyone deserving of being called one, are going to be against the concept of borders entirely. Governments or other oppressive bodies would be necessary for constructing/"defending" borders, so that's right out under anarchist ideologies. Different flavors of Marxists on the other hand have different ideas, but "workers of the world unite!" wasn't written by Marx in the Manifesto for nothing. National borders and national identity more broadly is seen as a reactionary concept that promotes an idealist conception of people over a class conception. Workers in different countries have far more in common with each other than the bourgeoisie from their own countries. A communist ideal society is stateless, classless, and moneyless (meaning money representating financial capital is not a standard of exchange). I'd say that leftists in general agree with that as a goal, but anarchists would not support using a "state" as a vehicle for reaching it. "Marxists" on the other hand (using Marxist loosely here, there are anarchist Marxists) would probably be okay with a socialist state existing to build towards that goal, and with a state tends to come state like things such as borders. That doesn't mean they'd enforce them or even draw them the same way as we do today, but it doesn't rule them out ideologically speaking. One of the central ideas of Marxist-Leninism is that workers must seize the power of the state in order to oppress the bourgeoisie (as opposed to the current arrangement where the bourgeois state oppresses the working class of course). Once their institutions have been thoroughly deconstructed Marxist-Leninists believe the state both can and should be phased out over time. Anarchists are either skeptical of this transition actually taking place or ideologically opposed to even a temporary state.