Washington ? When the union’s inspiration through the workers’ blood shall run,

There can be no power greater anywhere beneath the sun. Yet what force on earth is weaker than the feeble strength of one? But the union makes us strong.

That is the rousing first verse of the labor anthem “Solidarity Forever,” written in 1915 and sung to the tune of “The Battle Hymn of the Republic.” Ninety years later, “forever” has expired.

Pilots, flight attendants and other members of different unions are crossing the picket lines manned by members of the Aircraft Mechanics Fraternal Assn. The only solidarity in evidence is in the planning Northwest Airlines did in anticipation of the strike that the union called on Aug. 20.

Northwest is like the other “legacy” carriers – the older airlines with labor costs that cannot continue. The costs will be cut through negotiated cutbacks of benefits won by unions in palmier economic days and when it was believed that airlines could not risk a strike. Or the benefits will be cut unilaterally, now that Northwest has entered bankruptcy protection, joining Delta as the third and fourth of the seven largest carriers currently using bankruptcy as a management tool.

The fact that Northwest’s operations have been minimally disrupted by the mechanics’ strike is a function of foresight. Northwest had it; the leader of AMFA’s 4,430 striking mechanics, O.V. Delle-Femine, did not.

He has forfeited the support of other unions by poaching some of their members and disdaining other workers with lesser skills. The AMFA has no strike fund or medical coverage for its members, whose coverage from the airline has ended. Northwest wants $203 million worth of concessions from the union – a demand toughened by 15 percent from $176 million since the strike began – as part of the $1.4 billion it is seeking from all its unions. Northwest is using cheaper replacement mechanics, many of whom it trained for months – and not at all secretly – in Arizona.

Northwest, which has offered permanent employment to some of the replacement workers, seemed to have studied the playbook that Caterpillar used against the United Auto Workers’ strike of 1995. The strike failed after 17 months because of replacement workers and picket lines porous even to some union members.

Northwest might also have learned a lesson from Margaret Thatcher’s victory over the National Union of Mineworkers. Her government stockpiled coal near power plants and steel mills, and warned other users to prepare for a showdown. Nevertheless, the miners struck. Independent truckers prospered by distributing coal from mines that were still operating. After almost a year, the strikers capitulated. The mines were reformed and, although the number of miners was reduced by 40 percent, they produced 85 percent as much coal as the larger work force had produced.

American unions have long since lost their hold on the public’s sympathy. Time was, labor’s anthems could stir the blood. “Solidarity Forever” declared:

Is there aught we hold in common with the greedy parasite Who would lash us into serfdom and would crush us with his might?

Somehow those words seem, well, disproportionate to the labor strife that recently so stirred the blood of John Sweeney – head of the AFL-CIO, or what remains of it after the defection on Wednesday of a fourth large union – that he got himself arrested in a sit-in demonstration. The greedy, parasitic serfdom-lasher was New York University, which, it may be confidently said, is not a nest of reactionaries. The downtrodden serfs are graduate students.

They are teaching and research assistants who in 2000, the last year of the Clinton administration, won the National Labor Relations Board’s approval to unionize. About 1,000 did, and associated with the UAW. But by 2004 the composition of the NLRB had changed – presidential elections do matter – and it reversed its approval. Then NYU withdrew recognition of the union because it was breaking its promise to confine itself to economic issues and not inject itself into academic decision-making, such as the assignment of teachers to particular courses.

The graduate students say they will strike. And perhaps they will sing:

They have taken untold millions that they never toiled to earn,

But without our brain and muscle not a single wheel could turn.

But if Northwest can fly without the brains and muscles of unionized mechanics, how likely is it that NYU cannot function without graduate student assistants? A strike, to be effective, must withdraw skills that cannot be replaced, and there seem to be fewer of them than there once were.

– George Will is a columnist for Washington Post Writers Group.