A former US Ambassador to Ireland believed the Government imposed strict military inspections at Shannon Airport over fears it would hurt them at the polls, leaked documents have revealed.
James C Kenny asked superiors in Washington for advice on whether a new regime introduced in 2006 would force America to end the controversial stopover.
Whistleblower website WikiLeaks published a document which claimed closer examinations of US Air Force planes was designed to dampen public criticism ahead of the 2007 general election.
The cable from the Ballsbridge diplomatic corps, dated May 2006 and classified by Ambassador Kenny, said Shannon was a key transit point for US troops and "materiel bound for theaters (sic) in the global war on terror".
"Segments of the Irish public, however, see the airport as a symbol of Irish complicity in perceived US wrongdoing in the Gulf/Middle East and in regard to extraordinary renditions, a view that underpinned a recent jury decision to acquit the 'Shannon Five' protesters who damaged a US naval aircraft," it said.
The five anti-war protesters were acquitted in 2006 after being brought to trial three times and despite admitting causing damage to the plane.
The cable said Ireland gained diplomatic benefits and significant revenues by keeping Shannon open to the military. It said Shannon Airport was paid 10.3 million euro (£8.7 million) by the US in 2005.
The ambassador raised the issue to ask for the US government's advice on how it should respond to the tougher regime.
He also said he would seek clarification on inspections and the notification system, particularly in the light of Russia sending material to Venezuela.
The ambassador said the Irish public's main cause of concern was Shannon's use during the 34-day war between Israel and Hezbollah forces in south Lebanon.