He is, even if his rhetoric and analogies are sensationalist -- the points he's making are all too valid. The hard fact is, in modern America, we don't work for our employers (or ourselves, if self-employed), we all work for the government. If we don't give the government what it demands, we go to prison. This country didn't have an income tax until 1913 (save for during civil war), and I daresay that great American statesment of the founding era would have called it a form or species of slavery. Obviously, it's not the same thing as chattel slavery where someone owns and can sell you and your family, but it's an enslavement, in a clinical sense, to the government, which can imprison you if you do not hand over well more than a tithe of your earnings. Volokh ought to save his anger, outrage or moral indignation for that situation, not for Paul Roberts.
Volokh should read Walter Williams on slavery. There were many types of slavery practiced other than chattel slavery. Many other systems which are similar to slavery have been devised to extract the fruits of labor from the one who works: for example, worker debt schemes, piece works schemes etc...
PCR is pointing out that as taxes rise too high, the system looks more and more like one of those systems called slavery. Volokh was setting up a straw man argument and didn't fairly read PCR.
And who is more racist, someone who points out the intentional racial design of our immigration policy or those who created it?
The middle class nature of our society (that's middle class, not white) is being replaced with a populist or recipient style of thinking that I've come across in people from other countries. This is being done by immigration, by design. People who hate the US and hate the west are being brought in on purpose as societal change agents.
The middle class, nominally Christian nature of our society is being replaced with highly aggressive, might-makes-right types of behavior which is common in most of the third world. PCR is not racist to point this out.