This objection is sometimes raised, that anarcho-capitalism might not work because someone (who is wealthy?) might just try to create their own State, and anarcho-capitalism won't be able to prevent this.
I don't think this is a problem unique to anarcho-capitalism though, currently States are subject to secession or becoming worse, so anarcho-capitalism can't prevent a State from forming much more than the State can prevent being dissolved. There's somewhat of an equal problem, it seems like.
What are your thoughts on this objection that anarcho-capitalism can't work because it will just form into a State or State(s) again?
I agree it's not a problem, just a fact of life. If someone wants to make a "state" on their own property, that's their business. They will further need to convince other people or "states" to recognize them as one, if they so desire.
If they wish to steal land from individuals or force them to pay taxes, that is a violation of the NAP.
It doesn't, Anarchism is a moral foundation that allows me to reject such liberty-violating construct by violence (self-defense is always in effect when dealing with state agents).
A continually united purpose and a way to defend that state from forceful invaders
People get lazy, complacent, and look for an easy way out if not in the 1st generation then definitely by the 3rd or 4th generation. Forming your own state and having the full responsibility on every citizen can be burdensome so many will opt to give the power to someone they trust so that the citizen can spend more time on other things they want to do.
Just look at how most people cook in the kitchen. Usually it's one person doing the work, sometimes you have multiple people helping, but almost every time what is being cooked and how it's prepared is decided by one person.