Who's going to keep cryptos in control, the big question. It's actually the easiest question that was first answered in the introduction for Bitcoin. They are peer regulated and have no reason to be under any other purview such as any specific country. And for the reason they are decentralized, they really cannot be singularly under the purview of anywhere specific.
Any crypto that is very widespread among computers operating to record the ledger and pack it into blocks, is for all intensive purposes immutable. In order to change the existing ledger you need a 51% agreement among all of the miners, nodes, etc, to do so. This is why a crypto is stronger if it's around the globe with varied interests in the specific crypto. If only banks ran the ledger then they can vote to change it however they want. For that reason it should be specifically encouraged for everyone, for any reason, to run a device that is part of the global consensus. (presumably with incentives)
With a great many copies running in consensus they provide their own regulation to prevent double spending/false record – the original concept in Bitcoin's introduction. No one can change the ledger for personal reasons, only authentic transactions will show. At this point there is no need for external forces to engage – nor could they since it's global. And this type of regulation by peers can thread into other concerns such as ICO's. For example there is no reason why ICO's can't distributor a few of their tokens, pre-sale, to be reviewed on a variety of websites, pro & amateur, to check the contract for legitimacy.
A lot of people are calling for regulation out of fear when it comes to ICO's. But a question is how will regulation help if the weak point exists not in the crypto itself, but in the mediums we use to do things with them - the same mediums everything else is already on, and does get hacked. How many times have regulations returned lost money in regular security registered stock markets? It has happened multiple times in the crypto world from White-Hat hackers (good hackers). Where as regulation for securities are not 'security' themselves, or a compensation system for illegitimate activity. They are measures put into place that stop well established entities from convincing people to invest in high risk, as if it were low risk, with no more than a gentleman's promise on returns. Until a company with a very long track record of starting businesses with ICOs starts promising you it's safe for you to reverse mortgage your house to invest, regulations are at best a nuisance.
You can trade cryptos cheaply, like for nothing or minuscule amounts. This is important because the utility of them depends on the fact that dues have already been paid to the internet company, software, computer, building, state, etc… and they exist in a self regulated zone where the cost of movement is based on their own autonomy of existence and use – born out of world consensus. The cheapest trades in a security registered market are about $5. Clearly that pricing wouldn't work because it would cause nothing but inflation, and making the crypto no longer viable as a currency or utility. No one wants a Visa that went from 3% to $5 use-fee for buying coffee.
In our early stages of cryptos there has been some vulnerability. But it's pretty senseless to look to the past (ahem, 1920's & 30's) when we have answers in front of us. Why not have decentralized, blockchain based security, ICO sales? Well, we are getting there. Expect to see security that is blockchain based for ICO releases. As much as the ERC20 contract is standard, look forward to contracts that are used with webpages for ICOs; so that they cannot be hacked anymore than Ethereum or another crypto can be - smart contracts playing custodians of tokens.
It's the age of information and instant access, we don't need to pretend it is 1933. The world of cryptos will evolve and maintain itself with vested interest globally. This should be looked at extremely positively since it alleviates massive pressure for everyone involved. Celebrate the autonomy of choices and ability to engage in them. Celebrate White-Hat hackers that do amazing work when problems are detected and save people hundreds to millions of dollars in potential theft/loss. Be positive and recognize that cryptos' track record actually looks amazingly better than fiat's, and only improve at a rate so rapid that malicious people can't even finish their attack/theft before they get thwarted. The crypto world is looking good and on track to reliable self regulation, so long as it is allowed to develop out of its infant stage.