Senate Democrats were able to tolerate the government shutdown they orchestrated for only a few days before sheepishly agreeing to reopen it early Monday afternoon. This was the smartest move they made during their strange 60-hour protest.

On Friday, Democrats said they couldn't agree to a funding bill through Feb. 16 that included six years of funding for CHIP, and that protection for Dreamers had to be on the bill in the form of a new Deferred Action for Childhood Arrivals program.

By Monday, they said they could accept funding through Feb. 8, with six years of CHIP, plus a commitment to either an immigration deal by then, or a vote on a bill to replace DACA.

Democrats caved, and there are a few key reasons why:

1) Republicans didn't have much to give the Democrats

Democrats wanted to hold the government hostage to a big concession on immigration, and insisted that Republicans pay the ransom. But how much could Republicans really promise?

Immigration is one of the thorniest issues out there. All Republicans could do is promise to try and hold votes. No one can promise the final result. If Sen. Chuck Schumer, D-N.Y., brainwashed Majority Leader Mitch McConnell, R-Ky., into doing his bidding, the best offer possible was a pledge to hold a vote, which is all they got.

Democrats metaphorically tried to rob a poor man of a Rolex watch he didn't have. There was never a hope that they'd get what they wanted.

2) There was no immigration deal that could have been quickly stapled to the spending bill

Democrats said over and over that the spending bill should include a DACA fix because both parties want it, and the bill should include things that both sides agree on.

But that's a disingenuously simplistic reading of the Republican position. The GOP has long argued that it would take a DACA fix along with funding for the border wall and other immigration reforms.

There was no agreement on these issues. To get one would have taken at least the several weeks that Democrats agreed to in Monday's deal, and for all we know, several months more.

3) The Senate is the weakest leg of the stool on immigration

In a battle between the House, the Senate and the White House, the Senate is in the toughest spot. Trump can decide whatever he wants, and House Republicans can pass whatever they want as long as most of them agree to it.

But the Senate is a mess. The GOP has the narrowest possible majority, 51-49, and needs 60 votes to get anything done. And anything it gets done doesn't have to be accepted by the House or the president.

The Senate therefore has very little real power here, other than the power to hold something up. If a chamber can't pass its own policy vision, it has much less ability to influence talks.

4) The press wasn't buying the Dem spin

Democrats went to great lengths to spin their move as the "Trump shutdown," but even the party's staunch allies at the New York Times and other media outlets ran headlines saying Democrats voted against keeping the government open.

The Dem storyline was harder to spin because the actual spending bill that failed Friday was not something that drew raging Democratic objections. It funded the government, and authorized the Children's Health Insurance Program for six years.

The fact that there was anything close to a balanced debate over who was to blame for the shutdown marks a real victory for Republicans, who have been automatically blamed by the press in the last few cases. So the switch this time had to be worrying for Democrats.

5) Shutdowns are getting boring

We might be getting past the big shock of these partial government shutdowns. We know they end, we know all the furloughed workers get back pay, we know all the critical parts of government continue anyway.

It's hard to get excited about it (although we try). If they go on for a week, we learn such interesting fact as that 93 percent of the EPA is "nonessential." We're supposed to feel urgency over this?

The one way Democrats might have gotten some leverage over President Trump would have been to spook the markets. But the markets usually don't care about shutdowns, and that was the case this time around. The Dow Jones Industrial Average rose modestly on Friday as we were heading toward a shutdown.

Finally, in the age of Trump, there's a good chance that a partial shutdown is the least exciting thing happening on any given day.