The war on drugs is certainly dangerous. Making anything illegal makes it dangerous because it invites both the violence of the state, plus the violence that occurs in the absence of the state. The question is whether the danger the war on drugs has created is worse that the danger of those drugs being legal. Fortunatly, we have a very nice test bed here in the United States where we did make a dangerous drug illegal and then legalized it again. It would be interesting to run those numbers...
Most of us that will argue with libertarians until we're both (all?) red/blue in the face believe that government is useful, necessary and generally a good thing (TM) for a variety of reasons.
But do no wrong? That's a massive exaggeration. YOu can believe it does a hell of a lot wrong, in fact nearly everything, without believing we'd be better off without any government at all.
This is a totally fair question. So, let's say, for the sake of argument, that Al Capone's level of violence had nothing to do with his criminal syndicate. He just liked shooting people.
However, shooting people is expensive, especially given that they employed reasonably advanced weapons (sub-machine guns). So, he's not going to get as many bullets when liquor is legal. Also, though Capone is believed to have killed people, far more people were killed on his orders[0]. Without an unregulated and lucrative source of income, it's hard to see him having the money to hire people to kill others.
No one is saying that, absent the drug war, the cartel's enforcers would be in the peace corps. However, the extremely high street price of drugs finances a level of violence that would not exist otherwise. If you want an example, look at the history of Mexico in the last 20 years and compare it to any other nearby country.
Furthermore, while Al Capone could have found other crimes to orchestrate to make himself rich, he wouldn't have been able to perform those crimes as well as liquor smuggling, limiting his supply of cash (lets face it, he was probably doing those things in our history timeline as well as smuggling).
Alternatively, if we suppose some crime that he really did neglect in favor of smuggling, why did he neglect it in favor of smuggling? Because it was not as profitable or carried greater risk (in our history timeline, he was able to manage his risk effectively. He wasn't killed in the act and was only eventually caught for tax evasion. Had he been, say, robbing banks instead, he undoubtedly would not have lasted as long.)
Any way you slice it, prohibition made dealing with Capone worse than it otherwise would have been.
It's all about the money. There will always be a certain number of violent, power-hungry assholes out there, true. Banning drugs and thus enabling a black market in them means that people like that have a way to make money and create organizations dedicated to enforcing their will. Yeah, if we legalize drugs, they'll try to switch to something else to maintain their gangs and lifestyle, but nothing is as profitable as drugs, so there will be much less money available to such organizations, and they'll all either shrink dramatically or fall apart entirely.
It's also about how money influences people. Some people are irredeemably criminal/violent, but I think they're a minority. Most of the people in the market are probably following the money. They're doing it to make money, and they'll use violence if needed to preserve their market, but they probably don't have any desire in general to hurt people. Take away the need for violence by making it legal, and thus delegating violence to the police, and they'd probably be perfectly happy to be relatively normal businessmen.
Then again, maybe they'll just get involved in the Government instead :-/
Seriously? Giving monopolies to cartels drives massive profits. Cartels maintain actual military troops. It's hard to believe they'd have any source of crime remotely as lucrative without artificial monopolies making huge margins. Sure, they would do kidnapping, extortion, and so on, but that's not anywhere nearly the amount of easy money.
If the government granted Monsanto a license for weed, cocaine and poppy, the cartels would be cleared out in a month.
I fear they could coast on their cash reserves longer than that (and would desire to, instead of merely dissolve, to protect their remaining cash and avoid arrest), but otherwise I think you are exactly right. Kidnapping may be profitable, but it is nowhere near profitable enough to feed that beast.
I guess people who use the "they would just do something else" argument for cartels and prohibition mafias would be the ones to say that if the iPhone business goes bust within a year, Apple would just do something else anyway!
I mean are people so boneheaded to think that a massive source of revenue can simply be switched over without costs? The real world operates _on the margin_ (economic term).
The war on drugs is kind of this diorama encapsulation of everything that is wrong with our politics, media, and society.