Obama will be denied a similar opportunity because, for all the nation’s serious problems, none yet rises to the level of mortal peril. Obama’s reputation will necessarily be less exalted.

He is probably fooling himself if he thinks Obamacare, by itself, ensures him a spot close to the top in the presidential rankings. Medicare and Medicaid (far larger insurance expansions) didn’t do that for LBJ, so why should a lesser achievement do it for Obama? Indeed, if the implementation goes badly (coverage overestimated, costs underestimated), Obamacare could backfire.

Still, Obama’s enthusiasm for it is telling. Even without the 2008-09 financial crisis, he would have arrived in office just when the retirement of baby boomers was slowing the economy and raising — through Social Security and Medicare — government spending. The cost of government was increasing; the capacity to pay was decreasing. In these circumstances, Obama chose to expand government. His frame of reference was backward-looking: the fulfillment of a liberal agenda conceived from the 1930s to the 1960s.