Is US President Barack Obama even in charge of his own Secret Service security detail anymore?  And if he is, what was the point of this week's snub of Irish Sinn Fein party leader Gerry Adams after inviting him to cross the Atlantic Ocean for the umpteenth time to mark Saint Patrick's day?

On Tuesday, the delegation from Ireland paid a visit to the White House - as one does every Saint Patrick's week - to celebrate the close ties between the two countries and the importance of the Irish community in America.  But while outgoing Taoiseach Enda Kenny went right in and met with the President, Mr. Adams was told to sit and wait for a special security clearance - an inexplicable slight for someone who was instrumental to bringing peace to Northern Ireland in the 1990s after decades of political violence. 

Gerry waited for 90 minutes, even as party deputy leader Mary Lou McDonald and Sinn Fein Northern Ireland deputy first minister Martin McGuinness were both admitted.  After that, he declared that Sinn Fein "will not sit at the back of the bus for anyone", and with invitation in hand, he left.  

"I had received my usual invitation to attend the St. Patrick's Day celebrations in the White House and was pleased to accept," said Adams.  "When I arrived the staff at the White House informed me that there was an issue of 'security'."

"After two decades of traveling back and forth to the USA and countless meetings in the White House with successive US Presidents, this is an unacceptable development," Gerry added.  "It is obvious that there remain some within the US administration who seek to treat Sinn Fein differently."

The US Secret Service gave the lamest of excuses:  "Unfortunately, an administrative input error received by the Secret Service was not able to be rectified promptly," read a statement, expressing the agency's regret that the issue had not been resolved in a more "timely manner".

On Wednesday, Sinn Fein met with Irish-American members of the US Congress.  13 Republican and Democratic lawmakers then sent a letter of protest to the White House chief of staff, Denis R. McDonough.

"It is nothing short of astonishing that one of the principal architects of the peace process would not be allowed to attend a reception to which he was invited," the lawmakers wrote.

If someone in the Secret Service was freelancing his own foreign policy, it would be astounding in light of the agency's recent conduct - which has included drunken sex scandals and agents attacking members of the media.