We can never fully know if the National Security Agency's spying was justified, or how much it prevented crimes and atrocities from happening to Americans, on American soil. However, having personal friendships with people who work at the NSA, I believe that their intentions were honorable, kept us safe and secure, and therefore should be condoned.
The NSA has the role of protecting the country against terrorists. Since there have not been any major terrorist attacks in the United States since 911, the NSA has clearly been doing a good job. It is necessary for the government to take a hard line against terrorists by whatever means necessary.
Americans are very up in arms about the thought of being spied on. It has even been released recently (January 2014) that the NSA has been using apps to spy. While I don't personally like being spied on, they do argue that they're only interested in learning about people who pose a threat, so most of us having nothing to worry about. Aside from that, we have to remember that we are always being spied on when online. Many websites spy, especially e-mail accounts and sites like Facebook, to provide targeted ads and learn more about their customers. Their spying is far more intrusive.
What terrorists need most to do their work is secrecy. They can't risk being overt in carrying out bombings and so forth, they need the cover of darkness. Since telephony is the most pervasive means of communication today, that's the obvious place to look for them. NSA can't publicize their victory's because that would be showing their hands to the terrorists. Also, since we can't know where they are operating from, we have to root that information out from all forms of communication in order to discern which activities are a threat.
Today the media portrays them as crazies in caves with AK-47's (regardless of what the media calls them they are monsters) but what if tomorrow a 'terrorist was your neighbor, who happened to support the constitution.
All this data collection could simply allow a corrupt gov. to compile a hit list of anyone who politically opposes them.
My wife and I were in church ministry in Ethiopia in 1974 and watched the Marxist coup which overthrew the government of Heile Salassie. The Ethiopian people are famous for passing around news by mouth without changing it or exaggeration like we Anglo Saxons. After the coup, when i got into a taxi to go shopping, the usual packed taxi was totally silent. No one talked for fear of reprisals. This is now in progress with the NSA and the Obama regime. America is rapidly going silent except for the most banal conversation. Once 99% of us are silent, it will be easy to single out those still talking by rewarding the silent masses for finking. In fact, there may be no arrests for talking too much in the future. Americans may do as their Reps and Senators are doing..... Nothing. That is when tyranny wins, and Eric Holder is obviously winning. Welcome to the American republic of Mao Tse Tung.
In no way was the NSA spying program justified, and the program likely continues on right now. With that in mind, these programs were never proven to have captured potential terrorists or national security threats. Therefore, the NSA lied to the American people and gathered tons of information on innocent individuals.
NSA spying was not justified. This is because of the fact that the NSA spying is far beyond the realm of public privacy that the public should have. NSA spying on people is not constitutional, and should be stopped. The NSA has crossed the line with it's spying, and it wasn't justified.
The most large scale abuse of the fourth amendment, which protects a person's right to be free from unreasonable searches and seizures by the government, is the NSA collection of every Americans email internet and cell phone history. This massive intrusion of privacy has not stopped or prevented a single terrorist attack.
No, NSA spying was not justified, because it went far beyond the limits of the constitution. The NSA should only spy on people if they have a good reason to believe the people are engaging in a terrorist plot. The NSA should not generally be harvesting data from Americans. Just because it is easy to do does not mean it is justified.