President Barack Obama accepted the Nobel Peace Prize on Thursday in Oslo.

Obama said in his speech that war is sometimes needed to pursue security and peace and that violent conflict will not end in our lifetime.

He also said he was obligated to protect and defend the United States and that the use of force was sometimes not only necessary, but morally justified.

The following are videos of Obama's Nobel Peace Prize speech:

Obama's Nobel Peace Prize speech Part 1:

Obama's Nobel Peace Prize speech Part 2:

Obama's Nobel Peace Prize speech Part 3:

Obama's Nobel Peace Prize speech Part 4:

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