International law is colonialism

The initial chapters of the book build the links between International law and capitalism; International law and war (coercion, occupation, territorial agenda, setting up of nation-states); so it is not too suprising when we are told that:

"International law embodies the violence of colonialism and the abstraction of commodity exchange. It is not that the contribution of non-Western polities to international law has been obscured by colonialism, nor that (Western) international law's spread across the world is the result of colonialism: it is that internationalism is colonialism" (169).

I need to think on this some more but wanted to write this down before I forget this point as I read on - there's so much to discuss on this emphasis here. I have a few thoughts and questions but the ones puzzling me right now are these so I'll write them down. Forgive me if I change my mind about my own questions as I read on.

Some questions:

1) Under what circumstances/when/(any examples) is International law capable of good or is it ineffectual ultimately?

2) How is the exchange of commodities in a capitalist market different from the bartering of pre-capitalist structures? If we keep in mind what the values of exchange, property are. I am not too certain how to tell the two apart, other than the medium being money.