So the US doesn't care about Taiwan, it cares about China. Taiwan is just a tool.
Stating that the US has no allies other than Israel is unequivocally false.
If that's not an alliance, then you might as well say that alliances don't exist anywhere. (And maybe that is what you mean to say.)
Even the alliance with Israel can't compete with the alliance between the US and UK from World War I to now.
I'd argue North Korea & China have a closer relationship.