Hell, here's the Libertarian Party's tax policy:
When you pay taxes, do you do so voluntarily? Or do you do so because you are forced to do so? If you don’t pay your taxes, what will happen? Will you be fined further? Harassed by the IRS or other government entities? Jailed? The Libertarian Party is fundamentally opposed to the use of force to coerce people into doing anything. We think it is inherently wrong and should have no role in a civilized society. Thus we think that government forcing people to pay taxes is inherently wrong.
Libertarians advocate for voluntary exchange, where people are free to make their own choices about what to do with their lives, their time, their bodies, their livelihood, and their dollars. If Americans want to give money to the government for one reason or another, they should be free to do so. If Americans prefer to spend their money on other things, then they should be free to do that also.
Dear Libertarian, When you look at your tax bill, do you feel like a slave to the IRS? Republicans like to talk a good game about tax reform and fiscal responsibility but they are not committed to it. They have control of the House, Senate, and Presidency and if they wanted bold reform, they...
www.lp.org
How clueless does a person have to be to think America could function as a country united under a federal government if the only way government can get money is from Americans who "want to give money to the government for one reason or another"? Very little would give and there would be no way to plan for the future.
Aside.
You'll note this goes farther than the usual suggestion of these folks, which is that sales taxes and the like would be enough. (They usually frame it as "voluntary" taxation, but that's moronic. A voluntary sales tax would be: cashier rings you up, you are prompted to say whether or not you would like to pay the tax. Instead, it's just as involuntary as income tax: sure, the action that triggers the tax is voluntary - working (income tax) or buying (sales tax))
At any rate, just think about what passing that tax platform would mean. More or less immediately, the federal government would become insolvent and collapse. Nobody is going to lend to a country that has just done away with its ability to raise revenue. Do they expect all federal workers to just sort of volunteer or something? Manufacturers to donate needed supplies? Lunacy.
The best thing one can say about a Libertarian candidate is that they probably wouldn't get their way since congress would never do something that catastrophically stupid, even though it may be congress.