John Cornyn’s take on border wall money in the federal budget was customarily pragmatic. On Wednesday, he said it sounded like a deal was “coming together” and by Thursday, as passage of the federal budget neared, he was reading the details of the agreement.

What hath bipartisan action wrought? A winding path home, it seems, at least to an uneasy budget truce.

The senior senator from Texas, a Republican, labeled the diminished allocation in the budget — it was, perhaps, a quarter of what President Trump had sought in Fiscal Year 2019 — as a “down payment” on wall construction, although, unlike the president, he was not calling for a “wall” as such.

When the president says “wall,” Cornyn noted, he suggests a physical barrier. What is needed along the border to make it more secure — what will be built or organized, eventually — will involve multiple checkpoints on illegal border crossings: a wall or fence, in places; border guards or personnel in others; drones and technology elsewhere. The congressman to our east, U.S. Rep. Clay Higgins, R-Louisiana, a Trump ally whose district stretches to the Sabine River, has traveled the length of the U.S. southern border as part of a congressional mission and noted that, in some places, terrain itself is a barrier along elevated ranges.

Nonetheless, Cornyn said in a conference call with Texas reporters this week that the border can be porous. He said that’s why he takes border security seriously and, at one time, so did Democrats.

“This used to be not particularly partisan,” he told reporters.

On that same call, he suggested that Trump might sign a negotiated budget to avoid a second, partial shutdown of the federal government, then declare an emergency along the border and shuttle more money to the problem. That seemed inevitable Thursday and, in all likelihood, long before that.

On the whole, the border in itself doesn’t represent an emergency. Nor should it necessarily be labeled as such yet. But with large caravans of people pushing through Central America and toward the U.S., a border emergency might emerge, especially if political elements here and elsewhere urge migrants on.

A country $20 trillion in the hole can ill afford to open its borders to everybody. That’s not fair to U.S. taxpayers and it’s wholly unfair to generations ahead — think, “our own children” — who will have to grapple with such debt and perhaps worse, if immigration spins out of control.

Of special solace was that Cornyn said he and U.S. Sen. Ted Cruz, R-Texas, have both urged the president to lay off money intended to help rebuild Texas after Hurricane and Tropical Storm Harvey.

The president’s intentions to declare an emergency spawned immediate promises of federal lawsuits. That’s how we govern now.