Taxation is theft. "But who will build the roads" argument is really old and dumb, people are not some stupid monkeys who can't figure out things if no one guides them, there's nothing that can not be done privately and through voluntary cooperation (which is the same as privately). Roads, military, science and so on - all of it can and is done privately around the world. Government is exactly why Bitcoin was invented - you can't trust people with power and believe that they will do as they've promised, and even well-meaning leaders do stupid mistakes that cost billions. Just like Bitcoin have decentralized economy, some day people will decentralize power to the point when every individual will be independent from others.
Capitalist model does not work in every case but it's definitely the most sustainable.
Here is where capitalism would fail: * . A War ravaged community for example, that is starting a process of rebuilding will likely not find wealthy people within the community to build the roads, railways and schools. I think collective effort works best in this case. People will have to come together to contribute, money, builders, sands, water etc
* Very expensive projects(that aren't necessarily profitable short-term) may need government intervention.
* Some welfare schemes are necessary. Examples: welfare for the disables, poor/motherless kids, very expensive health treatments etc
The best way to PROPERLY fund such schemes are through taxes/contributions.