Story highlights David Gergen: Shutdown would hurt people in need, the U.S. economy and markets

Gergen: We've had shutdowns, but never a default, which may lead to global meltdown

Default could happen in three weeks, he says, so it would force parties to solve problems

Gergen: Shutdown would give Obama chance to take charge and get us out of this mess

Driven by a hard-line faction of conservatives, Washington has done something terribly stupid: shutting down the national government. Most of America is aghast. But it is also just possible that doing something stupid will help us avoid doing something truly dangerous.

Shutdowns are a lousy way to run a government. Just for starters, this one has cut off services to women and children in need, furloughed hundreds of thousands, further shaken the confidence of the public, sent a shudder through the financial world and created new storm clouds over the economy. And once again the world is wondering about our capacity for leadership.

But all of this damage pales in comparison with the danger posed by a second, lurking threat: a default on our public finances.

The United States has had 17 government shutdowns since 1977 and has generally recovered well. But we have never had a default. Experts, while not fully certain, are convinced that it could be hugely destructive -- even leading to a worldwide financial meltdown. Unless Congress and the White House get their act together, we could default in less than three weeks.

But a shutdown could have a silver lining. It could be such an electric shock to the political system that it forces the politicians in Washington to settle their squabbles before the default deadline.

What we know from past shutdowns is that not only citizens -- especially older ones dependent on Social Security and Medicare -- start raising hell, but so do business and financial leaders who see damage rippling across their economic interests. Politicians are increasingly seen as villains. Pressure tends to grow so unbearable that eventually Washington finds a solution.

Most of the pressure this time will be directed toward Republicans who have misplayed their hand. A new poll by CNN/ORC shows that 46% of Americans blame the shutdown on Republicans, seeing them as spoiled children. Thirty six percent blame President Obama, and 13% point fingers at both.

Seasoned GOP leaders across the country know that if the shutdown does serious damage, chances of Republicans picking up Senate seats in 2014 and the White House in 2016 could evaporate. Those leaders will push intensely for a way out.

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But Republicans are not the only ones who will come under pressure to find a settlement. So will Democrats, starting with President Obama. We expect our presidents to be leaders of all the people, not a single party or ideology. We want them to rise above the squabbling and keep us on track. The harsh rhetoric that the president has been directing at Republicans suggests that he is less interested in settlement than unconditional surrender.

Moreover, as Republicans make their counterarguments, it is becoming increasingly apparent that they have some valid questions. Is Obamacare truly ready for prime time? Shouldn't the two parties work together on the tax code? When is Washington going to get serious about overhauling the entitlement programs so they will survive for coming generations?

Yes, conservative hard-liners have chosen the wrong place to fight; arguments over Obamacare are no excuse to shut down the government. Yes, hard-liners like Sen. Ted Cruz, R-Texas, are creating deeper partisan divides. But Democrats can ill afford to continue rejecting any talks or negotiations.

Now that the shutdown has happened, Obama has a fresh opportunity -- indeed a fresh responsibility -- to seize the mantle of leadership and get us out of this mess. Instead of just blaming the Republicans, he should call in the leaders of both parties and in Lyndon Johnson fashion, keep 'em talking till they get a deal.

With the shutdown underway, the president has new leverage to say, "Look, we are here to negotiate a settlement so that we can reopen the government. We are not here to negotiate over a possible default; I have said all along that I won't do that. But those of you who have been listening closely know that I have also been saying that I am open to conversations about settling our policy differences so that we can keep the government running.

"Tax reform, entitlement reform and even some tweaking of the Affordable Care Act are on the table now. I have only two conditions: I will not accept a gutting of Obamacare -- we settled that at the ballot box in 2012 -- and any settlement here must include a pledge not to let the country go into default. So, let's get started."

Would it work? Who knows for sure? But one thing is clear: If enough Americans rise up now and pressure politicians in Washington to call off this circus, we could not only end this foolishness over a shutdown, but we could also avoid a truly dangerous default. And we could hold our heads up again.

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