Rarely does the world get to see the United States at its worst and best in such rapid succession.
As he took the podium at Thursday's memorial service for the victims of the Boston Marathon bombing, Barack Obama presided over a nation united in grief and defiance. He embodied everything admirable about America – its goodness, its statecraft, even its sense of humour.
"Our faith in each other, our love for each other, our love for country, our common creed that cuts across whatever superficial differences there may be – that is our power," Mr. Obama said.
Only hours earlier, the same President had stood in the Rose Garden to condemn what will go down as "a pretty shameful day." The Senate had just voted to block new gun-control measures in the latest demonstration of how deeply the National Rifle Association has its claws into legislators.
This time was supposed to have been different. December's massacre of 20 schoolchildren by a troubled 20-year-old with his mother's assault rifle truly traumatized the nation. A freshly re-elected President vowed to use "whatever power this office holds" to pass new gun laws.
It was not unreasonable to think the gun lobby would have the decency to comply or that at least enough members of Congress could be shamed into defying the NRA. So, Mr. Obama went big, calling for bans on assault weapons and high-capacity bullet clips. He demanded universal background checks to prevent criminals and the mentally ill from buying guns.
Never in his presidency had Mr. Obama used the bully pulpit with such intensity. For once, he wasn't leading from behind. In speech after speech, surrounded by survivors and parents of the dead, he invoked the fierce urgency of now.
Mr. Obama's failure to get the Senate to endorse even his least ambitious proposal – extending background checks to private gun sales and transactions done over the Internet – illustrated Washington's otherworldliness and this President's underwhelming powers of persuasion.
Many blamed Senate rules that set the bar for passage at 60 votes. It's more complicated than that. The calculation that goes into any senator's decision on how to vote is like a complex algorithm. And sometimes a yes is not really a yes, especially if a bill is already doomed to fail. The die was cast before the votes.
As Mr. Obama said, the gun lobby "willfully lied" by insisting the bill would have created a national gun registry. But the insinuation made it much harder for Democratic senators from states with widespread gun ownership, such as Montana's Max Baucus and North Dakota's Heidi Heitkamp, to vote for the bill. Nothing gets gun zealots worked up more than the prospect of the government you might one day want to overthrow knowing where the guns are.
The defeat of the background check amendment was bad enough. The outright rejection of bans on the sale of assault weapons and high-capacity clips (which allow shooters to unleash dozens of bullets without reloading) laid bare the futility of Mr. Obama's crusade.
Only 40 senators backed the assault weapons ban. More than a dozen Democrats voted against it – including the two from Colorado, where a crazed gunman toting an AR-15 just last summer killed 12 moviegoers and injured another 58. No one wants to find out what kind of tragedy it would take to get those politicians to change their votes.
Liberal Democrats are vowing to make gun control an issue in next year's mid-term elections. But the failure of the Senate bill to reach the House of Representatives, where it would have been defeated, deprives them of an argument to use against Republicans in swing districts.
The President's proposed measures were imperfect. The assault weapons ban would not have affected guns already in circulation. A universal background check would only have been as effective as the sketchy data it relied on. Unfit buyers would still have slipped through the cracks.
But the opponents of the gun bill did not vote against it because it didn't go far enough.
Many of the most fervent gun-rights advocates in Congress are the same legislators who back the toughest antiterrorist measures, the ones that deprive any suspect of his basic rights. They seem to place a higher value on the lives of people killed in places like Boston than on those that might be saved by a few entirely reasonable restrictions on the right to bear arms.