This time, the politicians are trying to work a repeal of the programme into a trade promotion authority bill currently before the US Senate, reports Vietfish.
The bill, nicknamed the fast track bill, is designed to assist with future negotiations of trade agreements.
The inspection programme, which has not yet officially come into effect, is seen as a major barrier to trade in these products from Viet Nam.
It is currently of particular interest because the Obama administration is currently working on a major new trade agreement, the Trans-Pacific Partnership, between the United States and several Asian countries.
This is why Senators John McCain and Jeanne Shaheen are pushing to add an amendment to the bill that repeals a catfish inspection programme that first went on the books as part of the 2008 Farm Bill, and later confirmed with the 2014 Farm Bill.
The programme took responsibility from the US Food and Drug Administration (FDA) for inspecting catfish, and transfers it to the US Department of Agriculture (USDA).
“The real aim was to raise costs for Vietnamese exports and drive them from the US market,” Mr McCain said on the senate floor on Tuesday.
Proponents of the programme have argued it is necessary to beef up inspection of the product, to prevent contaminants from causing public health problems in the United States.
Opponents, including Mr McCain and Ms Shaheen, have said there is no health threat, and that the programme instead will serve as an unofficial trade barrier to block imported catfish and protect domestic catfish producers in states such as Mississippi.
Mr McCain said Asian countries, whom the Obama administration is now courting in the new trade agreement, see the program as a trade barrier, too.
He added that the World Trade Organization (WTO) has indicated this programme, if it were to finally take effect, would be seen by the WTO as a trade barrier.
In addition, the Vietnamese government also has indicated it may retaliate against the United States with similar trade barriers to American export products such as beef. At the very least, Mr McCain said, Vietnam will likely appeal to the WTO for relief, “where it would probably win.”
Mr McCain also noted the program has not yet officially begun, but setup costs have already passed the $20 million (€17.9 million) mark, drawing the ire of multiple public officials and taxpayer watchdog groups.
Even the Government Accountability Office, has called the program wasteful on nine separate occasions. Amending the current trade bill to remove the program, Mr McCain said, will end the waste.
“If we don’t allow this amendment, we are really, really showing a degree of contempt and arrogance to the taxpayers of America,” he said.
Ms Shaheen also spoke against the programme, calling it wasteful and duplicative, and urged the senate to repeal it before it officially begins.
“This may be our last chance to solve this problem,” she said.
Senator Thad Cochran, who has been behind the programme from the beginning, said the new trade bill amendment was resurrecting an issue that the legislature had already decided upon.
“It has been debated and resolved in two separate Farm Bills,” he said.
He also cited a lack of inspections of catfish, noting the current system, relying on the FDA, allows inspection of only 2 per cent of catfish imports, risking exposure of Americans to hazardous contaminants.
“This is just not acceptable,” he said.
Senator Roger Wicker, who also supports the programme, cited the same statistic, saying, “That gives me pause as a consumer.”
Mr Wicker also denied that the program was enacted as a trade barrier to protect a small number of businesses in a few states.
“What this is about is food safety for Americans in 50 states,” he said.