I recall a story about Russia after the collapse....having difficulty collecting taxes....
so they started to hire out of work soldiers...as they could handle heavy weapons...
Subsequently went to a flat 13% tax rate and have no problems collecting taxes now.
‘Hire those least able or likely to pay to collect the taxes for you. There will no doubt be some corruption and graft - but most of the money will find its way to you - and the animosity of the people will fall upon the tax collectors and not yourself.’
-from a book by Steven Brust - paraphrased from memory.
Out of work soldiers don't have any money to tax and are thus unable to pay. They needed a job and collecting taxes (and handling heavy weapons) seems a task they would be admirably suited for.
13% is a great tax rate. Simple. Direct. Fair.