I've been arguing for years that nobody in national politics really believes in federalism--not as an end in itself. Federalism and devolution are just ideological weapons that officeholders and interest groups use when it's convenient to getting their way. Southerners didn't really care about states' rights; they cared about segregation. Major corporations wanted to be regulated at the state level when state oversight was minimal; now, when states are producing regulators like Eliot Spitzer and Washington is controlled by pro-business Republicans, being watched over by the feds suddenly looks constitutionally appropriate.
In making this argument, though, I've always had to make allowances for one exception--one person in a position of enormous power who really seemed to take federalism as an important principle, not just a political expedient. That one person was William Rehnquist. From his earliest days as a law clerk at the Supreme Court in the early 1950s, he argued consistently that American government couldn't work the way it was supposed to work if Congress kept preempting power and jurisdiction that the founding fathers had intended to be exercised at lower levels of the system.
He was still making those points when he became a justice in the early 1970s, often without much success. But in the 1990s, that began to change, and Rehnquist found himself on the prevailing side in a whole series of cases that questioned use of the commerce clause and other provisions to justify federal intrusion in what had previously been state affairs. He lost on a few of these issues too, even as chief justice. And some will argue that he cast doubt on his whole project in 2000 when he wrote the legally tortuous decision that overruled Florida's state courts and gave the presidential election to George W. Bush.
Looking at his career as a whole, though, I'm inclined to take Rehnquist seriously as the single important figure in modern American politics for whom the phrase "government closest to the people" was more than window dressing. Did he make the case effectively enough that others will pick it up in his absence? We will gradually find out.