Well, they push other countries all the time to take the their stances, outside of the voting system. Incentives to take their stance, 'threats' when they won't. Not all that spectacular but it's still not the way the system formally works.

You're talking about justice, but what if you have to decide a US policy, would you get involved in every crisis, knowing that it costs you a lot? You can't save the world.

Imagine the US cuts its relations with Japan, Taiwan, Philippines, India, and doesn't support it financially and with access to military technology. Don't you think it would be only a matter of time (not talking about 5 years of course) before China get dominance in the Western Pacific? I'm sure Taiwain would cut its relations with the US and start to grow towards China if they think the US can't protect them anymore.

(Edit: I didn't use your quotes to 'criticise' you, they were just convenient to give my perspective.)