The question as stated is a matter of possibility and not of intention. Someone that doesn't intend to upheld moral or ethical rules is still in the possibility of doing so.
I suggest an improved wording of the question: 'WILL NSA protect you by accessing your private info?'.
NSA is spying on people since its birth in October 1952. Since then many disaster happened where Americans suffered. For example, Oklahoma city bombing in 1995, lagurdia airport bombing in 1975, and 9/11 attack, Boston bombing in recent time. NSA is collecting data since 1952 which is its chief task. But it failed to protect Americans. So i don't think that there is a relation between private data collection and homeland security.