Mr. Blatt, you have written a well-balanced and judicious essay.
David Thomson seems to have missed a major point: why can’t gay couple raise children? dre also misses the boat. In reply I must point out the example of one of my local friends in a lesbian “marriage” (quotes used because Ohio explicilty prohibits even civil unions) recently bore a lovely daughter. She was artificially inseminated. Any gay woman can do the same. Any gay/lesbian couple can also adopt a child, or children.
Therefore using child-rearing as a defense for conventional marriage is not a useful argument, unless one holds that gay parents are in some way inherently defective. Aside from being, well, gay. Some folks seem to find that defect enough.
Dan, with respect to your snark about Arnolds veto: perhaps he did so because the referenced bill was statue law, not a constitutional amendment. Big difference.
