Since the 9/11 terrorist attacks, the U.S. has placed an added emphasis on public-private partnerships to improve security and assist with law enforcement. A recent skirmish between Apple and the FBI, however, has challenged the way private-sector companies interact with government agencies, promoting a strange mash-up of opposition, cooperation, and even a healthy dose of competition.On Monday, the Justice Department announced that it had successfully accessed data from the locked iPhone of Syed Rizwan Farook, who killed 14 people last year in a mass shooting. With this new development, the department's legal battle with Apple will be dropped.After sparring with Apple for weeks, the Department of Justice has apparently found a third party that has helped it decode the phone.