Justin Elliott follows up on my story about America’s Building Trades Unions and the oil industry co-opting the 99% movement in a push to pass the Keystone XL pipeline. The fact that 12,000 activists formed a human chain around the White House yesterday in a demonstration against the pipeline suggests that this co-opting isn’t gaining a ton of traction. Nevertheless, the radio and print ads in favor of “Jobs for the 99%” is particularly galling because of the participation of labor unions. Here’s some of Justin’s report:

Building Trades Unions spokesman Tom Owens declined to specify how much money is being spent on the ads beyond that it’s “a significant investment on our part.” Some of that money is presumably also coming from the oil industry, which is well represented in the Alexandria, Virginia-based Oil & Natural Gas Industry Labor-Management Committee.

In response, horrified Occupy Wall Street protesters on Sunday approved a statement of disavowal at the general assembly in Zuccotti Park, the main governing body of Occupy in New York.

“The leadership of the unions behind this campaign have made a public alliance with the oil industry and Tea Party funders,” the statement declares. “Big Oil and Tea Party billionaires are part of the 1% . The reference to the 99% is opportunistic and misleading. … We must dissociate from this attempt at co-optation by the 1% to preserve our movement as the 99%, and as definitive precedent to dissuade future attempts of co-optation.”

The AFL-CIO has declined comment on my story and Justin’s, and officially the federation, of which the Building Trades Division is an autonomous part, has no formal position on the Keystone XL pipeline. Unofficially, there’s a split in the labor movement. Some unions, like the building trades, support construction of the pipeline as a job creator. Others oppose the Keystone deal. AFL-CIO members the Transport Workers Union and the Amalgamated Transit Union have officially come out against the deal.

Support for the deal from the building trades hinges on the promise of jobs from constructing the 1,700-mile pipeline. But Brad Johnson reports that the promise of jobs – which the Chamber of Commerce stretches to an implausible 250,000 – is mythical:

These tremendous-seeming jobs claims are based entirely on a report by the Perryman Group, commissioned by the pipeline’s owner TransCanada, whose results have been described as “dead wrong” and “meaningless” by Council on Foreign Relations fellow Michael Levi and environmental economist Andrew Leach, neither of whom oppose the construction of the pipeline.

The only independent analysis conducted of the American job-creation potential of the Keystone XL pipeline finds that between 500 and 1400 temporary construction jobs will be created, with a negative long-term economic impact as gas prices rise in the Midwest and environmental costs are borne.

TransCanada’s own workers would handle most of the construction, and the steel for the pipeline has already been purchased from India. So there would be a temporary, tiny job boost at best.

So the building trades union would sell out the environment over a measly 500-1,400 jobs. Not to mention the fact that the economic impact would trend negative over time. It’s the ultimate in (largely illusory) short-term gains for long-term damage. And the building trades are partnering with Exxon, who basically runs the “Oil & Natural Gas Industry Labor-Management Committee” front group, to exclaim that approving the pipeline is a cherished goal of the 99% movement.