Income from ground rents are taxable last time I check Form 1040. So is income from exploiting the labor of others. If reward was tied to actual productivity, rather than the ability to bargain for a reward for productivity (in other words, if wages captured the entire productivity contribution of workers), you would have a point about the social justice of taxing non-rent income. Sadly, much of the benefit from worker productivity is transferred to those who "own" the output of that labor without just compensation - mostly because there are barriers to level bargaining (too few employers, barriers to entry, outright racism, sexism and classism). Income taxes serve the function of tapping these transfers and returning at least a portion of this revenue to those who should have been paid their fair share in the first place through government benefits. When these transfers are adequate, there is enough purchasing power in the economy to match productivity. When these transfers are not adequate - sometimes due to the failure to adequately collect worker productivity losses to the owners of capital - there is excess production compared to income. I also quibble with the compassion of your goal - lower cost land. The cost of land has been reduced quite enough in the last two years, thank you. Any sustained effort to keep it low will not be welcomed by either our elected officials or the public at large (many of whom owe more on their mortgages than the land values in their possession). Unless you are willing to put forward a dictatorship to impose an LVT, it won't fly in the current economy.