Labor Day is one of the two times a year (the other is April 15) that I diverge from my insouciant support of the social welfare state to quote from one or another worthy text. My Labor Day post is also in memory of Grandmother Laquedem, who as a final expression of solidarity with the working class died on Labor Day some years ago. Last year my selection was a portion of T-Bone Slim's rendering of the Hundredth Psalm. This year I'm more classically inclined, and offer an extract of The Wealth Of Nations, featuring Adam Smith on the taxation of wages. This bit is from Part II of Chapter II of Book V. Smith discusses the effect of taxation on the wages of common labor, then on artisans and professionals, and concludes with this passage. The word "officers" means government employees and not just military officers.
The emoluments of officers are not, like those of trades and professions, regulated by the free competition of the market, and do not, therefore, always bear a just proportion to what the nature of the employment requires. They are, perhaps, in most countries, higher than it requires; the persons who have the administration of government being generally disposed to reward both themselves and their immediate dependents rather more than enough. The emoluments of officers, therefore, can in most cases very well bear to be taxed. The persons, besides, who enjoy public offices, especially the more lucrative, are in all countries the objects of general envy; and a tax upon their emoluments, even though it should be somewhat higher than upon any other sort of revenue, is always a very popular tax.
Whether public officials remain "the objects of general envy" is dubious at best. I can envy a United States Senator (no particular one, however) more readily than I can a member of the Portland City Council or the state legislature.