Which created the most resentment among european nations?

Good morning!

The biggest producer of disagreements between European countries has always been the conflict over the territorial domain. As land was the main source of wealth, it became necessary to expand the domain of this resource. During the early twentieth century, imperialist conflicts (of dispute over the African colonies) coupled with the problems of exacerbated nationalism were the main motivations for the outbreak of the two great world wars.

Hugs!

The answer is crop yield.

They weaken the south vietnamese army.