Well free market theory would indicate that is impossible.
So some cartel spends huge amounts of money to drive up the difficulty and makes a large number of miners quit. They then start requiring high fees. There is no action without a reaction. The environment now is much lower difficulty and much higher fees = more profit per GH/s. Those miners who were "forced out" can now mine profitably so they turn miners back on and undercut the high fee miners.
Some mechanism of "price discover" for fees is necessary but we likely are some ways away from it. When the subsidy cut falls to 25 BTC per block fees will be more important however 90% to 95% of revenue will still come from the subsidy. The next subsidy cut in four more years will be more interesting and by the subsidy cut in eight years some fee "marketplace" will be important for the health of the network. Still talking about issues 5-9 years out is kinda premature when you consider BTC isn't even 4 years old yet.
One other thing I would point out is not all miners may be directly profit driven. MtGox makes money right? They make money because BTC are traded. In some hypothetical future where there is 100x as much BTC MtGox could be making 100x as much money. What happens to that profits if some cartel kills of Bitcoin? Wouldn't it be in MtGox interest to add hashing power to the network and accept free or low fee tx? They profit when Bitcoin is healthy. A cartel forcing excessive prices isn't healthy logically spending some of their profits to keep Bitcoin healthy makes sense.
You could even see something like a "priority merchant agency" form. An agency where merchants pay dues and submit a list of their addresses. They then contract with miners to give payments sent to those addresses high priority. Instead of paying a fee per tx they would allow their customers to send "free tx" and pay miners a flat monthly fee.
So some cartel spends huge amounts of money to drive up the difficulty and makes a large number of miners quit. They then start requiring high fees. There is no action without a reaction. The environment now is much lower difficulty and much higher fees = more profit per GH/s. Those miners who were "forced out" can now mine profitably so they turn miners back on and undercut the high fee miners.
Some mechanism of "price discover" for fees is necessary but we likely are some ways away from it. When the subsidy cut falls to 25 BTC per block fees will be more important however 90% to 95% of revenue will still come from the subsidy. The next subsidy cut in four more years will be more interesting and by the subsidy cut in eight years some fee "marketplace" will be important for the health of the network. Still talking about issues 5-9 years out is kinda premature when you consider BTC isn't even 4 years old yet.
One other thing I would point out is not all miners may be directly profit driven. MtGox makes money right? They make money because BTC are traded. In some hypothetical future where there is 100x as much BTC MtGox could be making 100x as much money. What happens to that profits if some cartel kills of Bitcoin? Wouldn't it be in MtGox interest to add hashing power to the network and accept free or low fee tx? They profit when Bitcoin is healthy. A cartel forcing excessive prices isn't healthy logically spending some of their profits to keep Bitcoin healthy makes sense.
You could even see something like a "priority merchant agency" form. An agency where merchants pay dues and submit a list of their addresses. They then contract with miners to give payments sent to those addresses high priority. Instead of paying a fee per tx they would allow their customers to send "free tx" and pay miners a flat monthly fee.
exactly what i was looking for. I just gave the a very unlikely case
