Why Does the Post Think It's Bad News that the Republican Budget Strategy is Falling Apart?

That is what readers a front page Washington Post news story on the budget must be asking. The piece notes the sharp decline in the budget deficit, then tells readers:

"That might seem like good news, but it is unraveling Republican plans to force a budget deal before Congress takes its August break (emphasis added)."

It's not obvious why the piece would use "but" in this sentence as opposed to "and." Obviously the Post considers it bad news that the Republican strategy is unraveling. Most pa...