The Supreme Court hearings on Obamacare begin this morning. Robert Sammuelson explains why the effect of the law on people's health has and will be negligible. But the political effect is huge.

Why did the prez push such a complicated, regressive and divisive law? Ego!

Considering the ACA's glaring -- and predictable -- economic and political shortcomings, why did Obama make it his first-term centerpiece? The answer seems to be his obsession with securing his legacy as the president who achieved the liberal grail of universal coverage. In his book "The Escape Artists: How Obama's Team Fumbled the Recovery," Noam Scheiber recounts a telling incident. Obama's advisers tell him he can be known for preventing a second Great Depression. "That's not enough for me," Obama replies.

The ACA is Obama's ego trip, but as a path to presidential greatness, it may disappoint no matter how the court decides. Lyndon's Johnson's creation of Medicare and Medicaid was larger, and he isn't deemed great. And then, unlike now, government seemed capable of paying for bigger programs. 

Sammuelson rightly points out that unless the Supreme Court rules 7-2 or better one way or another (and it won't), partisans from either side will attack the verdict. He's quite right.