I haven't played the story mode, and I was just wondering how far into the Story Mode the "Ambush" section is. For example, "there are 10 other sections before", etc.
Ambush is in Act 1 Scene 2. I believe it to be the 5th section
Source: http://guides.gamepressure.com/tomclancysrainbowsixvegas2/guide.asp?ID=4544 (Right Hand Side)