Each time the government uncovers a potential terrorist plot, the question arises: "To profile or not to profile." The Right declares "Most Muslims are not suicide bombers, but most suicide bombers are Muslim," and uses this as the argument for some sort of profiling. Inevitably, the Left decries racial or religious or other profiling as a means to identify potential threats. The argument is made that profiling is an unfair invasion of civil liberties. It is indeed. But it is also effective and efficient in its intended purpose.
Consider a group of 100 Muslims and 200 non Muslims. Suppose among the 100 Muslims, 8 are suicide bombers and of the 200 non Muslims, 2 are suicide bombers. The Right's claim is thus verified. Most Muslims are not bombers, but most bombers are Muslim.
Suppose the government sets a goal to identify 8 of the 10 total bombers, 80%. One way to do this would be to screen 80% of the entire population of 300, or 240. Screen 80 Muslims and 160 non Muslims. You would on average catch 6.4 Muslim bombers and 1.6 non Muslim bombers. (we can deal in parts of bombers - no pun intended - because we are extrapolating to a large population) In total, we catch 8 bombers and screen 240 people to get them, an equal percentage of Muslims and non Muslims.
If however, we screened all 100% of the Muslims we would catch all 8 bombers and would have reached our goal. We have thus, cut the number of screenings from 240 to 100, saved considerable resources, and caught the same number of bombers.
No matter what the actual percentages are, so long as the basic premise holds true that most Muslims are not bombers, but most bombers are Muslim, it will always be more efficient to screen a higher percentage of Muslims over non Muslims.
The real question, therefore, that lies behind the concern, is at what level is it "worth" the extra resources to preserve civil liberties. What equation or formula could there be to determine at what point does adding screeners or screening less efficiently with the same number of people result in a cost that is higher than the benefit of equality?
The answer is not "There is no cost too high." Any objective observer must realize that every day individuals, companies and governments make implicit or explicit calculations of costs and benefits and define some threshold beyond which additional cost is not worth the additional benefit. Consider Zero Tolerance policies for knives in schools. It's a nice City Council bumper sticker but it is completely disingenuous. There is no such thing. The tolerance may be very very low, but because budgets are limited and there are other demands on resources, the fact is, there is some limit to what is willing to be spent to prevent knives from showing up in schools.
The same principal must apply to profiling. I do not know what the numbers are, but there is some point at which the cost of not profiling is less than the benefit of equality. Liberals must be able to objectively discuss this issue. Ultimately, cries for equality must be supportable within the cost-benefit equation. It's cold hearted, but it's nothing more than the way thousands of decisions are made at all levels every day, by liberals and conservatives alike.