Ambassador Louis Susman and his wife , Marjorie , laid a wreath at the September 11 Memorial Garden in Grosvenor Square . Obama : ` ` Let us strengthen our resolve against those who perpetrated this violent act '' Family , friends of those killed in attacks read out in solemn prayer calls . Former Secretary of State Colin Powell speaks at Pennsylvania site . Events take place in New York , at the Pentagon and in Philadelphia , Pennsylvania .
Obama : ` ` Let us strengthen our resolve against those who perpetrated this violent act '' Family , friends of those killed in attacks read out in solemn prayer calls . Former Secretary of State Colin Powell speaks at Pennsylvania site . Events take place in New York , at the Pentagon and in Philadelphia , Pennsylvania .