South Carolina Gov. Nikki Haley blasted the National Labor Relations Board’s “un-American” lawsuit against Boeing in a conference call Thursday. Haley maintained that President Obama’s reluctance to weigh in on the merits of the suit is “the most cowardly thing I think any leader could do.”

The White House has sent mixed signals on the board’s suit against the airline manufacturer, Haley noted. On the one hand, she stated, the president has been “carrying the unions’ water” through various policy proposals. But Obama’s chief of staff and his nominee for Commerce Secretary both served on Boeing’s board of directors at the time the company decided to open a new assembly plant in South Carolina – the decision that spawned the NLRB’s lawsuit.

“This president owes us an answer, this president owes Boeing an answer, this president owes every business in this country an answer” on where he stands on that lawsuit, Haley insisted. “Silence is not leadership, and he continues to be silent on something that impacts our entire country.”

The only response from the president thus far has been a series of platitudes on the agency’s independence and his hope that the issue would be resolved. The Hill reported on the president’s statement in June:

“It’s an independent agency and it’s going before a judge, so I don’t want to get into all the details of the case,” he said during a news conference. “We can’t afford to have labor and management fighting all the time at a time when we’re competing against China and Germany and other countries who want to sell goods all around the world.

“The airplane industry is an area where we still have a huge advantage … I want to make sure that we keep it,” he added.

But Hayley and other conservatives have maintained that the rule will both drive businesses overseas, and raise the cost of goods and services here at home. As the Heritage Foundation’s Hans von Spakovsky and James Sherk explained:

If the NLRB and activist courts uphold the NLRB Acting General Counsel’s complaint, they will damage the U.S. economy. Forcing companies to either expand their unionized operations or not expand at all will reduce investment and job creation in the United States.

Unions essentially “tax” investments that corporations make, redistributing part of the return from these investments to their members. This process makes new investment less worthwhile. As a result, unionized firms invest less in physical capital and in research and development than non-union firms do. One study found that unions directly reduce capital investment by 13 percent and reduce R&D activity by 15 percent to 20 percent. Other studies find larger effects, such as the fact that newly unionized plants reduce capital investment by 30 percent—the same effect as a 33 percentage point increase in the corporate tax rate.

Forcing companies to invest only in unionized operations will reduce the total amount these companies decide to invest. Restricting competition restricts growth. The NLRB proposes to do this at a time when the U.S. economy remains sluggish and business investment remains weak. Private nonresidential fixed investment growth fell from an 8.6 percent rate in the last quarter of 2010 to just a 2.8 percent rate in the first quarter of 2011.