President Obama addressed the press on Monday afternoon at McCormick Place, Chicago, stressing that the city performed its hosting duties "magnificently" during the 2012 NATO Summit.

When asked about the protesters at the summit, Obama replied, "That is what NATO is here to protect ... that's what America is all about."

NATO leaders are gathered in Obama's hometown of Chicago, Illinois, for a summit to discuss NATO's mission in Afghanistan and international security issues, among other matters. On Monday, alliance leaders affirmed their commitment to an "irreversible transition" in Afghanistan.

Protesters have staged demonstrations on both days of the summit, marching through downtown Chicago and clashing with police over the weekend.

Related on HuffPost:

Loading Slideshow...
  • NATO family photo

    Leaders pose for the family photo at Soldier Field during the NATO Summit on May 20, 2012 in Chicago. (MANDEL NGAN/AFP/GettyImages)

  • Barack Obama, Anders Fogh Rasmussen, Sali Berisha, David Cameron

    President Barack Obama, center, and Secretary General Anders Fogh Rasmussen, point out Lake Michigan for British Prime Minister David Cameron, far right, during the group photo of NATO leaders at Soldier Field at the NATO Summit in Chicago, Sunday, May 20, 2012. Also on the riser is Albanian Prime Minister Sali Berisha, far left. (AP Photo/Pablo Martinez Monsivais)

  • Hillary Rodham Clinton, David Cameron, William Hague

    Secretary of State Hillary Rodham Clinton speaks to British Prime Minister David Cameron, left, and British Foreign Secretary William Hague during the 2012 NATO Summit in Chicago, Monday, May 21, 2012. (AP Photo/Philippe Wojazer, Pool)

  • Barack Obama, David Cameron

    President Barack Obama talks with British Prime Minister David Cameron before a meeting on Afghanistan during the NATO Summit, Monday, May 21, 2012, in Chicago. (AP Photo/Carolyn Kaster)

  • Angela Merkel, Julia Gillard, Johanna Siguroardottir

    From left, German Chancellor Angela Merkel, Australian Prime Minister Julia Gillard, and Iceland's Prime Minister Johanna Siguroardottir talk during the International Security Assistance Force (ISAF) meeting on Afghanistan at the NATO Summit in Chicago, Monday, May 21, 2012. (AP Photo/Pablo Martinez Monsivais)

  • World Leaders Take Part In NATO Summit In Chicago

    CHICAGO, IL - MAY 21: President of Azerbaijan Ilham Heydar combs his hair as he arrives for a meeting on Afghanistan during the NATO Summit at McCormick Place on May 21, 2012, in Chicago, Illinois. As sixty heads of state converge for the two day summit that will address the situation in Afghanistan among other global defense issues, thousands of demonstrators have taken the streets to protest. (Photo by Kevork Djansezian/Getty Images)

  • German Chancellor Angela Merkel, right, and Greek Foreign Minister Petros Molyviatis, center, arrive to pose for a photo at the 2012 NATO Summit at McCormick Place, May 20, 2012, in Chicago. (MANDEL NGAN/AFP/GettyImages)

  • Hamid Karzai

    Afghan President Hamid Karzai, second right, chats with NATO Secretary General Anders Fogh Rasmussen, left, as Afghan Foreign Minister Zalmai Rasoul, 2nd left, and Afghan Defense Minister Abdul Rahim Wardak, right, look on during the 2012 NATO Summit May 21, 2012, at the McCormick Place convention center in Chicago. (MANDEL NGAN/AFP/GettyImages)

  • Francois Hollande, Anders Fogh Rasmussen

    French President Francois Hollande, right, meets with NATO Secretary General Anders Fogh Rasmussen during a bilateral meeting at the Radisson Blu Hotel before attending the opening session of the NATO Summit in Chicago, Sunday, May 20, 2012. (AP Photo/Yoan Valat, Pool)

  • Hamid Karzai

    Afghan President Hamid Karzai attends a working session on the second day of the 2012 NATO Summit in Chicago, Monday, May 21, 2012. (AP Photo/Philippe Wojazer, Pool)