My post is only concerned with income tax. Government revenue up until that point had been provided by sales tax and tariffs. Income tax for 99% of Americans did not exist. Income tax is just another revenue stream, promised to be temporary. This isn't a general gripe about taxation, touching anyone's bank account, or generating revenue. There is zero misunderstanding of economics. The post was about a special tax for the general populace, that was introduced as temporary. That "temporary" part is a lie.

And history: Income tax in the US dates to 1894. The 16th Amendment was ratified in 1913. A very premature response to WWII.

Income is not the only taxable quantity; tariffs, excise, property, wealth, and estate taxes are among the options.

Not to mention simply spending a lot less on things the federal government doesn't need to be involved in to begin with.

Sorry?

Such as?

We could start with all the things the federal government wasn't involved in prior to the enactment of the income tax.

You're not answering the question.

The world has changed somewhat since 1894.

Maintaining over 700 military bases across the world, endless war (handouts to Military-Industrial-Congressional Complex companies), corporate welfare, foreign aid, public art, Africa, etc...

OK, that's a set of specifics, though for the first you might find much of that has some justification (economically, not necessarily morally) via geopolitics of both raw materials (petrochemical and the Harbord list) and trade.

FYI the last three items amount to about 2% or less of Federal spending. All discretionary spending was 16% in 2016:

https://upload.wikimedia.org/wikipedia/commons/thumb/c/ca/U....

Excluding entitlements (Social Security, Medicare, debt service) it's still minuscule:

http://memepoliceman.com/wp-content/uploads/2015/09/viper-re...

You asked what the government could spend less on. I answered the question. What more do you want?

You've not given specific cases, and your hand-wave ignores reality.