Confused about the back-and-forth between the House and Senate over the budget shutdown that threatens the entire American economy? Allow us to explain, using the Legos on our desk.

Let's say, for the sake of explanation, that this is the funding for the federal budget.

It's not that clean and orderly, of course. And the budget at issue in Congress right now has big holes from where the sequestration led to across-the-board cuts.

Like any budget, it's composed of a number of pieces.

A lot of it, for example, goes to defense. (Not to scale, since defense was one-fifth of the budget in 2011.)

And some of it goes to the Affordable Care Act, or Obamacare, which itself has a number of pieces.

That's it at right. That's Obamacare.

And then there are all sorts of other things that are included: parks and health and veteran's services and nutrition, for example.

So the funding proposal under discussion looks more like this, with all those little pieces added in and still those holes from sequestration.

On September 30, the budget was set to expire. So Senate Majority Leader Harry Reid, a Democrat, advocated for passing a resolution continuing the ugly budget we've been working with all year. This is the so-called "clean CR," a resolution without amendments.

At first, House Speaker John Boehner, a Republican, seemed to go along with that. His second-in-command even wrote a statement praising the passage of the sequestered budget in September.

But then Sen. Ted Cruz of Texas got involved. He'd spent the summer touring the country with the Heritage Foundation, arguing that a shutdown was preferable to providing any money for Obamacare.

Cruz convinced his conservative allies in the Senate and House that this made sense. So, with not much time left before the budget ran out, Boehner proposed continuing the budget as it was, minus the Obamacare part. 

It passed the Republican House.

Cruz (and everyone else, really) knew the idea wouldn't pass Reid's Democratic Senate. So after being pressured to do so, he gave a 21-hour speech that essentially just burned the clock.

And sure enough, Reid and the Democratic Senate said, "No. Pass the whole thing." 

Boehner tried again. This time, he proposed delaying part of Obamacare, repealing a tax on some medical devices, and taking out a mandate that employers cover contraception.

Reid and the Democrats had the same response. No. Pass the whole thing.

That same day, September 30, Boehner tried again. How about delaying the individual mandate and revoking the subsidy the government gives staffers to buy health insurance?

No, the Democrats replied. Pass the whole thing.

Shortly after midnight on October 1, Boehner tried one last idea. Same as the last proposal, but including a conference between the two chambers to work out a longer-term plan.

No. The whole thing.

By then, the government had shut down. So the Republicans turned to another great idea from Ted Cruz: Why not pass bills funding parts of the government?

This seemed smart politically: make the Senate say no to things people loved. Like, at first, money for the N.I.H., the Park Service, and money for the District of Columbia. 

(These took two days to pass due to a procedural hiccup.)

And then they added more: benefits for veterans and money for the National Guard.

... Money for FEMA and for nutritional programs.

But the response from the Democrats has been the same: No. The whole thing. After all, they argue, anything else is simply the Republicans holding some aspect of the government hostage to demands they can't pass in Congress.

So here we are. The Democrats want a vote to pass the full budget; Boehner won't let it happen

The shutdown is one week old.

The end.