According to Wikipedia.org, "In September 2013, the incarceration rate of the United States of America was the highest in the world at 716 per 100,000 of the national population." This indicates that America is a prime believer that those that commit criminal acts need to be certainly punished. Or does it? The reason why there appears to be some legitimate debate about this, is the fact that the American jurisprudence allows, for certain crimes, notorious or not, a multitude of ways to petition the courts, so as to delay judicial actions within courts, so that justice is delayed again and again; or else through negotiation between lawyers and the court, decisions are thereby molded and subsequently rendered; or through plea bargains; so that the effect is that what may appear to be certain as in the law as written, does not nearly appear to be so certain, as the law so exercised.
The reason that this matters is because, those that believe, that the illegal actions that they are taking are subject to being interpreted in a manner in which those lawbreakers will not personally have to suffer, or suffer much because they are, for whatever reason, effectively above the law to the degree that the law will not impact them negatively as it would for someone of lesser stature or position, then there clearly is no punishment certainty in that case, which therefore makes the punishment severity of the law so written, pretty much irrelevant. Further to the point, when those that have a lot of influence and/or money, are able to buy time by that influence and money, so as to delay justice, in which, while such justice is pending, they are able to thereby live their lives as if they weren't even charge of a crime, then any punishment certainty or punishment severity have taken a backseat to the fact that the wheels of justice are not even in motion, and those that are able to buy time in the justice world, are often those that are able to buy an acceptable result to that justice, when such is eventually rendered. Finally, there are those that are protected in regards to their illegal actions by virtue of such being done through the means of a corporate entity, so that that whatever punishment is finally determined, will not hold anyone personally accountable, but rather will be a decision that will involve a corporate, but not a personal, penalty.
So too, when it comes to punishment and the severity of such, those that suffer the most from this severity are those that are the poorest and least able to vigorously and competently defend themselves in a court of law. The fact that so many are incarcerated for so long in America, indicates that severity does not stop criminal activity, although it does do a very good job, of severely punishing those that have no influence, no status, and no hope.
If, American concentrated far less on punishment severity and far more on punishment certainty, in which, connections, money, influence, and the protection of corporate entities were not permitted to play a part in American jurisprudence then this could very well impact the amount of crimes so committed in this country, for when people that commit crimes, know for a certainty, that should they be caught, that justice for them would be sure, swift, equal, just and fair; of which no appeals would be permitted, then that certainty would make them far more guarded in what they do, or contemplate so doing, for when criminals know that there is no legitimate way out for what they have committed, the price that they pay has become appreciably higher.