The federal government shutdown is now the second-longest in history. We’re on Day 21, and if it lingers into early November, Congress could surpass the current record of 35 days – from, as it happens, the first Trump administration. Who knows if we’ll get there. There is a premium in these debates on appearing resolute. That means neither side telegraphs that it might fold – right up until the moment one does. But there are also a number of dynamics pushing us toward an especially prolonged shutdown right now...