While the U.S. does not extend invitations to overseas politicians and government leaders for inaugurations, it is understood that Adams made the transatlantic journey in his capacity as a private citizen.
He was accompanied by long time party colleague and adviser Richard McAuley.
“The United States has played a consistently significant role in the Irish peace process over the last decade.
“President-elect Obama has already committed to continuing U.S. support for the Irish peace process,” Adams said before leaving Belfast.
“The new U.S. president has also made positive comments on trade and investment, and has acknowledged the need for immigration reform.