Each state would have build its own military, its own currency, its own FBI, CIA, white house staff..redundancy and waste! 

You may have a currency risk though.

Canadians with their exchange rates on currency have cooled off some buying in the U.S. but other countries have heated up investing here.Lot of people in CA are willing to pay low caps because simply they do not need the money.

Of course China can just deflate their currency by 25 percent, making the tariff a moot point.

Stable currency, 5.

Finding trustworthy people to manage it, and currency/language barriers.

@Dave Currence , I came across your post while searching feedbacks for marketing companies.

That has a currency to it as well.I am 14 years in the business.

Aside from being the most precious, non-renewable resource, time is our universal currency.

It makes sence for South Africans to invest in a stronger currency in a safe vehicle like property.