The Democratic National Convention, which begins today in Charlotte, faces a different challenge from the one that faced Republicans last week.
Mitt Romney and company had the duty to explain what they intend to do if he becomes president. The Obama Administration must answer questions about what it has done so far and would do in a second term.
Inevitably, that discussion requires a focus on the economy, which is still mired in unemployment amid an anemic recovery. Stimulus spending, while dismissed as a failure by Republicans, arguably kept the country from toppling into the abyss of insolvency.
However, defensiveness about the administration's record does not answer for the future. What can be done now? And how can spending be curbed to address the deficit, which is unsustainable over the long run?
Clearly, tough choices need to be made. It's not enough to accuse Republicans of seeking to wreck Medicare and Social Security. The multitrillion dollar question is: How can President Obama pursue a progressive agenda when the nation has no ready money?
Other questions stalk the Democrats. The war in Afghanistan continues to claim American lives and drain the treasury, long after the rationale for it has evaporated. Although Mr. Obama has drawn down troop strength there, the United States is still wasting blood and treasure on a hopeless cause. Why?
Mr. Obama is accused, with some justification, of following or embellishing the national security policies of George W. Bush. What is his answer?
Although Osama bin Laden has been killed and the victims of 9/11 avenged, the use of unmanned drones continues to be prolific, raining death on terrorists and innocents alike. What about Guantanamo Bay, a source of shame that remains open as a notorious holding pen despite Mr. Obama's earlier promises to close it?
Congress has resisted efforts to close Guantanamo, but that raises another question: How does Mr. Obama intend to lead the nation forward when the House and Senate have every chance of remaining bitterly divided? How can the President forge agreements with lawmakers who regard compromise as anathema?
Mr. Obama is not the postpartisan idealist whose eloquence captured the imagination of America four years ago. He has been diminished and made ordinary by circumstances, not all of them of his own making. His hope of change too often has turned out to be a few coins rattling in poor people's pockets.
To be fair, few other presidents came into office at a harder time. Few presidents have had to contend with such bitter political opponents, much of their criticism not only false but also unhinged from reality.
It is a wonder that this President has achieved anything at all, and of course Mr. Obama has had successes. But is the best argument for giving him a second term the claim that his challenger might be worse? That is an unhappy prescription for winning an election.
The Democrats' challenge at this convention will be to give voters positive, detailed, exciting reasons to vote for them. To that end, Mr. Obama's famed oratorical skills are needed as never before.