This talk, originally delivered at a University of Houston symposium on tax crimes, asks why the norms that underlie our laws against tax evasion are so seemingly unstable. Ten reasons are offered: (1) tax evasion is difficult to distinguish from tax avoidance, (2) the conduct that underlies the crime of tax evasion is complex, (3) choate and inchoate liability are conflated, (4) a heightened mens rea of "willfulness" is required, (5) the level of enforcement is low, (6) enforcement practices are arbitrary and uneven, (7) criminal and civil violations are not clearly distinguished, (8) there is a sense that "everyone else is doing it," (9) taxes are demonized in our political culture, and (10) the tax code is perceived as unfair and tax revenues are thought to be misused. It is also suggested that part of the reason the norms against tax evasion are so unstable is that there is confusion about exactly why tax evasion should be regarded as morally wrong. To that end, the debate over the moral content of tax evasion is revisited and extended.