I don't know if that is a Secret Service agent in the left of this frame, but I think I know what he's thinking: "Don't touch the President."
The Daily Mail has an excellent story on Presidential security for the visits.
Full coverage of the Ireland visits.
Kevin Lamarque / Reuters
A woman puts her hands on the cheeks of U.S. President Barack Obama after he spoke at College Green in Dublin May 23. Obama sipped a pint of stout and cuddled babies on Monday as a tiny Irish village on Monday welcomed home "a long lost cousin" with an outpouring of affection. Hoisting a glass of Guinness at Ollie Hayes pub as fiddle music played, Obama thus began a four-nation tour of Europe with a celebration of his ancestral roots.
If you watched this on television today, you probably didn't see the bulletproof glass around the podium.
Peter MacDiarmid / Getty Images
US President Barack Obama speaks at a rally in College Green on May 23 in Dublin, Ireland. U.S. President Obama is visiting Ireland for one day. Earlier he met with Irish President Mary McAleese, Taoiseach (Prime Minister) of Ireland Enda Kenny and visited his ancestral home in Moneygall, County Offaly.