So Harry Reid just announced that a deal has been reached on a short term temporary reauthorization of the Federal Aviation Administration. That’s unquestionably good news, but the basic dynamics of the situation remain unchanged. The current deal does not resolve underlying disagreements — in particular over the House GOP’s demand that the long-term reauthorization weaken unions.

Which means that Democrats will find themselves in exactly the same situation in a month that they faced in recent days: House Republicans will be in effect holding up FAA reauthorization to get what they want, and labor unions will be demanding that Democrats not budge if they want labor to work for them in 2012.

Here’s Harry Reid’s statement:

“I am pleased to announce that we have been able to broker a bipartisan compromise between the House and the Senate to put 74,000 transportation and construction workers back to work. This agreement does not resolve the important differences that still remain. But I believe we should keep Americans working while Congress settles its differences, and this agreement will do exactly that.”

The compromise stipulates that the Senate will pass the temporary reauthorization that already passed the House, one that includes cuts to rural airports that Dems had opposed, but Transportation Secretary Ray LaHood will use his authority to waive those cuts. This is a creative solution, but it is only a temporary one, and it means the larger battle will be rejoined in a month. The House will not have to act anymore on the temporary solution. But House Republicans will certainly reiterate their insistence on the provision that makes it harder for unions to organize railway and airline workers by counting workers who have abstained from voting on unionizing as No votes.

Dems deserve credit for not buckling in this fight — so far — as unions like the Communication Workers of America have successfully demanded. But it needs to be loudly restated that this has become a make-or-break issue for unions at a time when labor is very unhappy with the national Democratic party and has plenty of strategic incentives for channeling resources away from Federal races and into state-level battles. Dems have postponed it for now, but a major test for organized labor still lies ahead.