A few weeks ago, a colleague in my department asked me whether I thought there was a realistic chance that the government would shut down due to various Republican-Democrat disagreements, some related to healthcare, some not. At that time, I indicated that I thought that a shutdown was highly unlikely. Key House Republican leaders like John Boehner had played important roles in the 1995-1996 shutdown. So I reasoned that there was enough institutional memory left about how badly that maneuver had turned out for Republicans that the party leadership would not risk making the same mistake again.

I was wrong. Clearly.

I admit this, because I think it suggests a valuable point. Normally as a political science professor I love to be asked my opinions. I practically begged people to talk to me about the election in 2012. But when it comes to the shutdown, we are in uncharted waters.

Some attribute the cause of the shutdown to the election of an assertive House Republican majority in 2010. That is only part of the story, though. The origins of the shutdown stretch much further back in time. The current chasm between the Democratic and Republican parties is the result of a polarization process that began nearly half a century ago when Southern Democrats first started to abandon their party over civil rights. At the same time, divided government, which has actually been a somewhat rare occurrence over the course of American history, has become a staple of the contemporary political landscape. And then these broader trends have intersected with increasing budget pressures that have been visible since the mid-1980s. As a result, the U.S. has witnessed a series of escalating fiscal battles, with the shutdown only being the latest one. Few seem to remember that in 2006 Obama himself voted against raising the debt ceiling in the midst of a tense conflict with the Bush White House over spending.

Given these larger forces, it is extremely difficult to predict what the final consequences of the shutdown will be. To borrow the words of Donald Rumsfeld, it seems to me that when we’re talking about the shutdown there are more “known unknowns” then there are “known knowns.”

Consider, for instance, the politics of the shutdown. Some argue that the Republicans are pursuing a losing strategy, just like they did in the mid 90s. That may turn out to be true. And yet… polls shows that Democrats are sharing much of the blame for the government closure. A CNN poll released this week revealed that 63 percent of respondents were angry at the Republicans, but 57 percent of those questioned also claimed to be angry at the Democrats. Republicans are also opposing a healthcare law that remains unpopular. According to the most recent aggregation of polls by Real Clear Politics, Americans oppose the Affordable Care Act by a margin of about 50%-40%. So who “wins” in this conflict? That’s a known unknown.

Consider also what this means for Speaker Boehner. Some argue that Boehner will be diminished by this crisis because the events of the past few weeks have proved he is either incapable or unwilling to ride herd over the more conservative members of his party. And yet… some Tea Party Republicans are expressing more confidence in Boehner than they have in the past. Might he emerge strengthened? Another known unknown.

Finally, consider what an actual deal that ends the impasse might look like. The smart money appears to be on the Republicans capitulating before October 17th, the date on which the Treasury Department says it will no longer be able to pay America’s bills. Business leaders and academics agree that a default would be calamitous for the world economy. And yet… some Republicans seem perfectly willing to test that theory. I don’t think we can entirely rule out a default. It’s yet another known unknown.

There is an old analogy that has been used by political scientists to describe American politics. Some say politics are like clocks- predictable and rational. Others argue that politics are more like clouds- unpredictable and random. In the end, what I am trying to say is that, to me, politics is looking more like a cloud every day.