Why Roberts did it
It’s the judiciary’s Nixon-to-China: Chief Justice John Roberts joins the liberal wing of the Supreme Court and upholds the constitutionality of Obamacare. How? By pulling off one of the great constitutional finesses of all time. He managed to uphold the central conservative argument against Obamacare, while at the same time finding a narrow definitional dodge to uphold the law — and thus prevented the court from being seen as having overturned, presumably on political grounds, the signature legislation of this administration.
Why did he do it? Because he carries two identities. Jurisprudentially, he is a constitutional conservative. Institutionally, he is chief justice and sees himself as uniquely entrusted with the custodianship of the court’s legitimacy, reputation and stature.