Moreover, if you think that cartels can arise & sustain themselves on a free market then we'd have to presume that there's no point in arguing for freer markets at all, may be we all should join the liberals in their pursuit of regulationism!
Yes, cartels don't work in a free market, they can only be maintained by force.
But that's my point - what's to stop the security firms from forming a cartel and maintaining it by force?
Anarchists just assume they won't, even though they will have the means (they are in the
business of using force - being
security firms), and its obviously profitable for them to do so.
Nonetheless, just to play Devil's Advocate if you will; I don't know how a minarchist can attack AnCap by saying security firms may overstep their bounds because as we know very well, governments always overstep their bounds, there's no basis for believing that the governments won't continue doing that in the future. So in that sense, security firms aren't necessarily worse; if anything, it's the better alternative because when the firms do overstep their bounds, they won't have the veil of legitimacy that often gets in the way of people revolting against governments. For all of its trangressions, most people in America probably won't want to revolt against the government but let's say it was just a firm then may be even some of the liberals (who love government so much) would have joined in the fight.
Let's say if America was just a geographical area owned by a for-profit firm, then people wouldn't see it as part of "us", they would rightly see it as "them". There would be no liberals asking for welfare because it is a for-profit company & not the "benevolent" government that's supposed to look after everybody; & even if they did ask for it, you could always move to somewhere else with more favorable conditions, which is not as easy to do under the current system of governments.
As far as forcing people to pay for firm's services, seriously, a minarchist who supports forcible extraction of taxes to fund government shouldn't really be arguing about this! Besides, you know, U.S. government is like one of two governments with a draconian policy of taxing its citizens' income no matter where they live, & for this, the U.S. government frequently threatens other governments.
It may seem strange that I'm criticizing anarchism because it will lead to the re-emergence of the state, while myself proposing that we keep the state.
But
not all states are equal. Some are worse (much worse) than others.
If we create a minarchist state, well then we have the best possible state. Yes, it will probably get worse over time, but there's nothing to be done about it.
Whereas, if we abolish the state, some new state will reemerge, and
who knows what kind? It may be much worse than a minarchist state. It can't be better. And it too, whatever it is, will get worse over time.
EDIT: to return to one of your points...
So in that sense, security firms aren't necessarily worse; if anything, it's the better alternative because when the firms do overstep their bounds, they won't have the veil of legitimacy that often gets in the way of people revolting against governments. For all of its trangressions, most people in America probably won't want to revolt against the government but let's say it was just a firm then may be even some of the liberals (who love government so much) would have joined in the fight.
I agree, but that's a double edged sword. Yes, the people might be more likely to revolt against a new state with no historical sense of legitimacy et al, but for precisely that reason the new state might have to be more brutal. If you look at the history of the state, it began as a terribly brutal, overtly criminal gang of robbers and murderers. Over time, as it was able to indoctrinate people, it could sheath the iron fist a bit, to the point that now people hardly realize that the state is backed by brute force. A newly formed state in the formerly anarchic society, if the people are looking like they might revolt against it, is likely to go full Ivan the Terrible on them. For a current example of what a primitive state in the process of establishing itself looks like, consider Africa. In some ways it's better than a well-established state (doesn't have the means to enforce a really totalitarian program), but it is far from libertarian in character. It's very weakness makes it vicious (out of necessity for self-preservation).
So, again, I get your point but that can go either way.