This one took some time to get right, but here it is...
The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no warrants shall issue, but upon probable cause, supported by oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.
United States Constitution
Most thumb-sucking crybaby liberals will hate this analysis of the Fourth Amendment just because it is not going to crucify the president and the NSA. In fact, it might vindicate them both.
The right of the people
Again, we are talking about the people of the United States, as in "We the people of the United States" who were mentioned in the Preamble. The people referenced there are not just any people, they are the people of the United States -- legal, rightful citizens of the United States, not unlawful enemy combatants or illegal aliens. Those who are not in this country according to the rules and laws of immigration do not have, nor are they entitled to any of the rights guaranteed by this Constitution.
"to be secure in their persons, houses, papers and effects"
Americans' private stuff is just that; private. You do not have to give out your name, phone number, address or any other personally identifiable data that you do not want given out.
"against unreasonable searches or seizures"
The operative word here is "unreasonable." It means without justification or just cause. An unreasonable search is a search conducted by an agent of the government solely on the grounds that it can be done. It requires there be some justifiable cause for the search. Such justifiable causes include imminent danger of an individual or a group or in the interests of national security and safety.
"shall not be violated"
No government agent or agency can conduct itself otherwise.
"and no warrants shall issue"
Prohibits the random handing out of warrants.
"but upon probable cause"
Limits the warrants that are issued to be kept within reasonable limits.
"supported by oath or affirmation"
Keeps some level of accountability to the agent or agency requesting the warrant. This prohibits them from going and getting a warrant just to say they have the warrant. They have to be willing and able to back up the reason for the warrant.
"and particularly describing the place to be searched, and the persons or things to be seized."
Limits the scope of the warrant. Meaning that if one thing is being sought, another, unrelated item or person cannot be included.
It must be made absolutely clear that this amendment is designed to protect citizens of the United States from unreasonable searches and seizures. It means, for example, that a person's computer cannot be confiscated by law enforcement without a warrant and without a reason (such as evidence that the user is soliciting sexual favors from a minor).
It also means that an individual cannot be arrested without a warrant or a reason (such as evidence that the person actually engaged in sexual relations with a minor). There is absolutely nothing in this amendment that prohibits any agency from monitoring a person or persons from a distance. If this were the case, then the use of cameras to ticket drivers who fail to stop on red lights would be prohibited. It would also forbid the use of any means of law enforcement from determining that a driver is speeding.
It would also prohibit law enforcement from engaging in stakeouts to observe criminal suspects. It is this freedom of monitoring which is extended to law enforcement that is the basis for the NSA wiretapping and nowhere in the Fourth Amendment is this, or any other kind of monitoring prohibited. To proclaim the NSA's monitoring of telephone conversations between individuals in the United States and individuals in a nation known to harbor terrorists is a violation of the Fourth Amendment is a gross misunderstanding of the Fourth Amendment.
Returning to the example of speeding. Is a person really secure in his or her vehicle? After all, vehicles are not explicitly mentioned in the amendment. Is a horse-drawn wagon not a vehicle; a mode of transporting people or things from point A to point B? Such vehicles were very much in existence when this amendment was ratified, yet they are not mentioned. Interpretation has extended the right of protection under the Fourth Amendment to a person's vehicle. So if a person is allowed to behave as he or she wishes in a vehicle that is capable of operating at high rates of speed, why is the highway patrol allowed to use radar to determine if the person is exceeding the posted limit? The person is committing a misdemeanor when he or she exceeds the speed limit and yet law enforcement is allowed to monitor that activity. Furthermore, the highway patrolman who writes that speeding ticket doesn't need a warrant to stop that driver. However, when a person uses a telephone something that did not exist at all when this amendment was ratified to commit a felony mass murder, the suspect can do so without having to fear scrutiny from law enforcement? You're thinking, "yes, but the guy in the car could have an accident and kill himself or other people." Okay, but isn't plotting to blow up an office building and kill large numbers of people on purpose worth some consideration? The highway patrolman who stops someone from speeding is no more violating the Fourth Amendment than is the NSA agent who observes a terrorist plotting to murder innocent people. In fact, the NSA has more of an obligation because the NSA is hundreds or thousands of innocent lives whereas the highway patrolman is only saving a few.
We are so quick to demand that we be protected from drivers with bad judgment and ready to accept monitoring by law enforcement, yet we cower in horror at the idea of letting our federal law enforcement protect our nation from groups wishing to do the nation harm. One job of our federal government is to "provide for the common defense." It's written right there in the preamble of the Constitution. We must allow our government to do its job or there won't be a United States to defend.