[foepys]

You try to equate the current Visa, Mastercard, etc. to the current Bitcoin. This is not possible because Visa alone handles like 100,000 times the volume of Bitcoin. As soon as Bitcoin&Co. become serious currencies, the incentives for manipulation rise. When eventually no new Bitcoins will be generated, all miner incentives come from mining blocks for the transaction fees. How do you want to protect the chain? How much will a single transaction cost to pay for the power to prevent this manipulation by working faster than the "enemy"?

If you raise the block size to put more transactions into a single block, you will end up with a normal banking system because nobody can carry the whole blockchain with them to pay and has to trust providers that manage wallets.