The grand promise is what one occupier, Brendan Burke, described to BuzzFeed as “a day without the 99%.” But in the city where the movement was born, it’s already suffering from what has emerged as one of Occupy’s signal weaknesses, the lack of ability or interest to make alliances with liberal institutions. Despite public solidarity, there’s little relationship between the Occupy movement and organized labor. And as a result, even the most progressive New York labor leaders say their members will not participate in the May 1 strike.

“It won’t happen,” said Stuart Appelbaum, president of the Retail, Wholesale and Department Store Union and one of the first labor leaders to embrace the Occupy movement. “They are not working with the unions in a serious way yet; nor are the unions working with them in a serious way. And it is the wrong strategy.”…

Here, however, the 1947 Taft-Hartley act, which sets the conditions between labor and management, protected some labor actions but outlawed general strikes, and make national Occupy calls for a May 1 general strike a very heavy lift…

The difference isn’t just one of tactics: Despite public expressions of solidarity, labor leaders say privately that they’ve been frustrated by their inability to build a long-term relationship with the leaderless movement. Instead, they’re beginning to plan a day of protest later this year in support of the right to organize.

None of the union leaders BuzzFeed spoke with said they’d been contacted by occupiers about plans for a strike, a silence that has made the grand talk of a general strike even more puzzling to people whose members are familiar with picket lines.