President Trump told congressional leaders in a meeting Friday that the partial government shutdown could go on for “months or even years.”

It’s a sign of just how desperate things are beginning to look. Consider the facts on the ground: Trump doesn’t like to lose (though maybe he’s tired of all this winning?), and he’s said he won’t take anything less than $5 billion. House Speaker Nancy Pelosi said the most she’d give Trump for his wall is $1. Yes, that’s one dollar. Trump won’t reopen the government without his wall, which is not made of concrete, but steel slats, which he thinks should be more palatable for Democrats. (It’s not.)

It’s hard to imagine how this will all get resolved. So, let’s run through the various scenarios:

1. Trump simply caves

If political pressure mounts, congressional Republicans could lean on Trump to reopen the government without border wall funding. In this scenario, he’d probably fight for an assurance from Senate Majority Leader Mitch McConnell (R) that the Senate GOP would prioritize border security in the next few months. Then, if the Senate reached a compromise on border wall funding and a permanent fix to the Deferred Action for Childhood Arrivals program, or DACA, it’s conceivable that Pelosi might feel an incentive to push something through the House. If Trump thought this was possible, he could cave and sign a clean bill to reopen the government.

2. Congress overrides Trump’s veto

Another possibility: Senate Republicans could take up the clean funding bills the House passed this week and send it to the president. Trump has said he would veto it. But Congress could override if the bills pass both chambers with two-thirds support. It might be a stretch in the Senate, where 19 Republicans would have to vote with the entire Democratic caucus. McConnell is unlikely to bring up a bill that doesn’t have majority GOP backing. But there are enough Republicans up for reelection in 2020 in swing-ish states that it could be done.

3. A concession from both sides

In the very recent past, Democrats offered Trump some options. Last month, they were prepared to give him $2.1 billion for border security, but Trump said he would accept nothing less than $5 billion. Democrats have since gained control of the House and dug in, saying they won’t give any money at all for the wall. But maybe leaders could be persuaded to go back on their pledge if the White House accepted the lower dollar figure. There’s no incentive for Democrats to do this unless they decide the shutdown is simply too harmful to let go on.

4. A big bargain

The Democrats could revive their deal from last year that would have exchanged $25 billion toward a border wall for a path to citizenship for Dreamers. Trump initially signaled interest but was talked out of it by the hard-line anti-immigration people around him. That deal is probably looking pretty good right about now to Trump. It could appeal to the Democrats, who have made protecting the Dreamers a priority.

5. It doesn’t end

In this most unlikely of scenarios, neither side folds and the agencies remain shut down through the end of 2020, when there’s a presidential election. If a Democrat wins, he or she could reopen the government. If Trump wins, he wouldn’t need to placate his base anymore and might give up on his fight.

But if this actually happened, if parts of the government remained closed until January 2021, that would mean more than 800,000 federal employees plus thousands of government contractors would go for two years without pay for their work or without work, full stop. Despite Trump’s threat of a years-long shutdown, there’s no way Congress lets that happen.