There can be no argument about the debates: They have become critical turning points in the 2012 presidential election. GOP nominee Mitt Romney recast the race with his widely acclaimed dominance in his first meeting with President Obama.

In Tuesday night's second debate, however, multiple public-opinion polls confirmed Obama as the winner. Gone was the hesitant president of the Denver debate. On Long Island, Obama went on the attack in a New York minute, and stayed there.

The theatrics are important -- if not in solving the issues, at least in selecting a president. Like many voters, the dwindling "undecideds" are likely to go with their guts as much as their heads.

As with the first debate, however, all the drama was about a dénouement on Election Day. The real story will begin on Nov. 7, and will continue through four years that will define America's future. And just as with the first debate, and the vice presidential matchup, Tuesday's thrust-and-parry left unanswered key questions about what economic sacrifices voters should expect, and what political compromises elected officials need to make.

Obama's robust defense of how he's cleaned up the mess he inherited was a welcome reminder that although progress is frustratingly slow, the economy is inching ahead. But Romney was also right to point out that some of this progress is due to spiraling borrowing, which has created two major policy challenges: In the short term, the "fiscal cliff" the country faces at the end of the year, and in the long term, the nation's unsustainable debt.

Both candidates' evasions disappointed. Obama's complaint about a noncompromising Congress is legitimate. But he once again failed to explain how the next four years would be any different.

For his part, Romney finally gave a glimpse -- although not a plan -- of how he would pay for even more tax cuts. He suggested a possible cap to itemized deductions, with voters choosing which ones to exercise come tax time. That's hardly a blueprint, however, which is why Obama was right to refer to Romney's deficit plan as a "sketchy deal." Romney's reassurance that "of course they add up" was résumé-based, not policy-based.

Voters, and Congress, deserve more specifics. And the candidates don't have to invent them: Instead, they can embrace the sensible solutions advocated in the Simpson-Bowles plan, which realistically advises that making difficult choices now will avoid devastating choices later.

On several other issues, each candidate scored points. Romney was strongest when pressing the president on lackluster job growth, noting at least six times that 23 million Americans are out of work. But Romney was discordant on health care. He boasted how nearly every child was insured under his Massachusetts health plan. Yet he continues to promise to repeal Obamacare (as even the president now calls it), which was based on Romney's Massachusetts success. Romney similarly obfuscated on immigration policy, contradicting his more rigid primary-season positions.

While Tuesday's debate was billed as covering both domestic and foreign policy, most questions reflected the pocketbook concerns dominating the campaign. What little was said about international affairs was backward-looking: Romney called Obama out for the administration's shifting narrative about the terrorist attack on our Libyan consulate, which killed four Americans. Obama may have won on points -- aided by a real-time fact check by moderator Candy Crowley -- but Obama must deliver to the victims' families, colleagues and fellow citizens his promised accounting of what happened, and how the State Department didn't report it accurately from the beginning.

He'll have his chance on Monday, when the final debate focuses on foreign policy. Both candidates should also answer hard questions about Iran, and about whether the United States is moving down the path to yet another major Mideast war.

While they're at it, they also should take the time to address the fundamental questions on their deficit-reduction, economic and political strategies that they dodged this week. After all, no less an expert than former Joint Chiefs Chairman Admiral Mike Mullen says that the debt "is the single biggest threat to our national security."

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