We agree regarding taxing businesses. Added to your point is taxes make domestic businesses less competitive by increasing the cost of production.

Your argument concerning currency has merit to the extent that governments have no obligation to keep the money supply limited. On the other hand, abuse of their ability to add to the money supply leads to an unwillingness of to transact in that currency for fear of its devaluation. So, governments are not quite as free as you suggest.

In fact, one benefit of a "balanced" budget is it instills confidence in the currency as a "store of value". In that sense, the Canadian government does need revenue to insure it is reducing demand enough to support its purchases without setting off inflation.

Regarding taxing oil companies, I have a slightly different view. Coming from an insurance background, the energy industry along with most natural resource companies inflict a certain amount of damage to the environment. That will need to be remediated at some point in the future. Those costs should be estimated, and "reserves" set up to fund the remediation in the future. If the government opts to hold those reserves not trusting the company to do so... it is not a big deal to me... alternatively, the government could mandate a company set up a reserve as it does for pensions in order to fund this future liability and not produce artificial profits in the short term and which will get distributed and not be available in the future.

As an aside pollution is simply the byproduct of human activity. Whether its human waste, trash, industrial waste, or mining waste. I think over the next 100 years, one of the booming industries will be to use incredibly cheap energy from nuclear and solar sources to turn waste into valuable resources. Waste only becomes waste because we don't know how to use it profitably... yet.