LOWER MANHATTAN (WABC) -- A congressional hearing in Lower Manhattan stirred memories of 9/11 Tuesday, with NYPD Commissioner William Bratton and former Mayor Rudy Giuliani testifying."Mr. Chairman, it's a great honor for me to be here. This is not just a museum, it's sacred ground," Former New York City Mayor Rudy Giuliani said.In the shadow of hallowed artifacts from 9/11, Former Mayor Giuliani was the first to address the House Committee on Homeland Security taking stock of the lessons we've learned since and just how prepared we are for the next threat."I do think in our city the state of preparedness is about as good as it can be," Former Mayor Giuliani said."I feel very secure in what the NYPD, and the FDNY, and the Port Authority Police have done," Rep. Peter King, (R) New York said.Part of that readiness is recognizing how the threat has changed."Many of these new threats are all internet driven," a committee member said.Police Commissioner William Bratton acknowledges the growing viral threat, and is making the point that so-called "lone wolves", inspired by terror groups like ISIS via social media, present a huge challenge."It's a Pandora's box, areas of terrorism," Police Commissioner Bratton said.This hearing just days before the 14th anniversary of the terror attacks also focused on the human toll of 9/11, with many stressing the importance of continuing to care for those who were there when the country needed them most."It's up to you members of Congress to speak up and support the Zadroga Bill," said Lee Lelpi, of the September 11th Families Association.