The question is rather: Is taxation justifiable theft? A necessary evil? Libertarians tend to argue that it's wrong regardless the intentions. Taking someone's property without their permission is unethical, no matter how good you want to do with it. Others, who support social contract theory, argue that it's necessary and should be seen as "voluntary obligation".
There is no right or wrong answer (un)fortunately. Feel free to speak out loud.
My stance on this is that both "groups" bring some compelling arguments on the table, in favor of their ideology. I don't know. I think there's a place where we draw the line. For example, nowadays, I think we've crossed that line (towards more government of course). I don't think we need that much government into the markets.
To answer the question in the subject, "Is taxation theft?" - when you put it like that, yes technically it is.
But, just because it's defined as that, doesn't mean it's bad or good. From my perspective looking at tax in a "good or bad" or "white or black" approach, is just too much of an oversimplification and it's neither. To be boring, it's both.
Taxation is necessary, as Governments acting as central bodies need money to create order and peace. Without Governments, there would be a lot more instability and chaos. To employ people to work in Government, tax is required to pay for their wages, but more importantly so that the remaining surplus can be used to allocate to the society to make it better. Improve road safety, subsidized transport options, and where possible free healthcare.
I think the question that really needs to be asked is: "At what
point does taxation become theft?"
In most countries, income taxation is not a flat % rate, regardless of how much you earn. It scales, as you earn more, you pay more tax. This to me is just insanity. Why should someone who works harder, is more productive, and delivers more outcomes to benefit society, be taxed more? It slightly disinsitives actually doing a good job? And the income tax rate can be 50%+ in some cases? I really don't agree with this. If there was just a flat 20-25% tax regardless of how much you earned, I would be happy with this.
The other issues with tax, is that Governments will apply it to anything they see fit.
Buying a car? You must pay registration tax.
Buying a house? You must pay land tax.
Getting a mortgage? You must pay tax.
Importing items internationally? You must pay tax.
Buying gas? You must pay import tax.
Buying cigarettes or alcohol? You must pay import tax.
All of the indirect taxes, is what really kills it for me.
At that
point, it's too much.