If the U.S. were a confederation, which of the following would be a problem it might encounter? Buying and selling goods would be confusing. Deciding who is in charge during war would be a problem. Trading between states would be a problem. Schools would not have the proper funding.
I would say Deciding who is in charge during a war. If we were all together and fair spread of power it would ruin the idea of a confederation to decide a leader.