It's also really telling that any mention of costs from TSA or individual TSO's comes to what the testing equipment would cost the agency. Apparently the cost to pax of throwing away completely harmless liquids, of buying the airport $4 per bottle "screened" water vice the Albertson's $1.49 a skid brand, of the time spent (and expense to the airlines) of dealing with checked bags that would have been perfectly safe in the cabin is apparently not worthy of mention.
A more rational policy is apparently being implemented with powders. Perhaps someone could consider adapting this to liquids.

Leading Causes of Death in America - 2006

1. Heart Disease 631,636 (26 percent)
2. Cancer 559,888 (23.1 percent)
3. Stroke 137,119 (5.7 percent)
4. Chronic Lower Respiratory Diseases (Lung Diseases) 124,583 (5.1 percent)
5. Accidents 121,599 (5 percent)
6. Diabetes 72,449 (3 percent)
7. Alzheimer's Disease 72,432 (3 percent)
8. Influenza and Pneumonia 56,326 (2.3 percent)
9. Kidney Disease 45,344 (1.9 percent)
10. Septicemia (infection of the blood) 34,234 (1.4 percent)

Combined, the top ten causes of death in the US accounted for 76.5 percent of all deaths combined. The following causes were numbers 11-15 on the list. None of these accounted for more than 1 percent of total US deaths in 2006.

* Suicide
* Chronic Liver Disease and Cirrhosis
* High Blood Pressure
* Parkinson's Disease
* Homicide

I came across a numbingly-titled but intellectually honest paper called: “Incorporating Assessments of Terrorism Risk in Homeland Security Resource Allocation Decision Making: Closing the Gap Between Current and Needed Capabilities.” Its 10 pages are worth reading by anyone who cares about homeland security and risk, and who believes “the problem” is fixable. (The paper is available here; it appears to have been written to support an April 13-16 conference called “Risk-Informed Decision Making for HLS Resource Allocation;” information about what looks to be a thoroughly interesting conference can be found here).

Some excerpts from the paper [and my overly simplified interpretations]:

“Despite the best efforts of numerous experts from the government, industry, and academia, fully effective and transparent integration of risk assessments into DHS homeland resource allocation decision making remains an elusive goal.” [The theory is not working in practice.]

“The risk construct … [Risk = Threat x Vulnerability x Consequences] is logical, intuitively appealing, and consistent with conceptualizations of risk used in other domains. However, uncertainty inherent in deriving estimates for its components in the case of terrorism risk continues to compromise its usefulness in DHS resource allocation decision making. As a result, terrorism risk assessments have not played the prominent role they were expected to play in DHS resource allocation decision making. More robust and defensible methods for generating required inputs for this terrorism risk construct are required if it is to become an important factor in homeland security resource allocation decision making.” [The theory sounds good, but the data to use it aren't there.]

Risk Management:

“Significant perceived shortfalls in our current ability to generate defensible estimates of the threat of terrorism, terrorism vulnerability, and the consequences of terrorism continue to hamper DHS’ ability to effectively incorporate terrorism risk assessments into its resource allocation decision making process. In addition, predicting and/or measuring the risk reduction effect or payoff of terrorism risk management initiatives remain a complex and unresolved challenge.” [We can't defensibly calculate the values the formula needs; we also can't figure out the effect of reducing risk.]

Threat:
“[The] statistically oriented, historical frequency approach [to determine threat] is useful for that portion [of the] DHS’ “all hazards” mission space associated with natural catastrophic and accidental events. However, [that analytical approach] does not apply to the threat (i.e., probability of attack) of terrorism. Risk analysts assessing the risk of terrorist activities are not faced with accidental random loss-inducing outcomes or acts of nature. They must deal with the potential for harm and/or loss deliberately inflicted by intelligent and adaptive adversaries willing to operate outside normally accepted patterns of behavior. Simply identifying all potential terrorists is a monumental challenge. Predicting their behavior – i.e., which targets or kinds of targets terrorists may strike, how they will choose to strike (i.e. weapons and/or threat vector), and when they will strike is an even more daunting and uncertain element of terrorism risk assessment.” [Terrorism is a really different kind of threat.]

Vulnerability:
“Assessing the vulnerability of potential terrorism targets might seem to be a theoretically more tractable problem. However, it requires detailed knowledge of the target, the nature of the terrorist attack, and the circumstances under which it will occur. Thus, vulnerability assessment involves many of the same uncertainties encountered when assessing the intentions and capabilities of potential terrorist adversaries. Even where credible estimates are possible, the sheer magnitude of the task of assessing the vulnerabilities of every potentially lucrative terrorist targets in our open society is overwhelming.” [Everything is vulnerable to something.]

Consequences:
“Predicting the consequences of terrorism events also presents difficult intellectual, philosophical, and emotional challenges. Most previous catastrophic risk assessments have limited their prediction and/or measurement of consequences to direct effects which can usually be estimated in relatively straightforward, transparent, and reliable ways. These direct effects typically include human fatalities, injuries, and the direct economic cost of the physical damage inflicted. However, it is widely acknowledged that terrorism events usually result in a broad range of secondary or indirect effects or costs that can be more extensive, and often more important and long lasting….Not only are these secondary or indirect effects of terrorist events difficult to predict or measure, but knowing how to prioritize them, and/or to compare them with the consequences of catastrophic accidents and/or natural disasters remains an unanswered question with complex societal and emotional dimensions.” [Consequence streams approach singularity.]

Risk Mitigation Effectiveness/Cost-Effectiveness:
“Assessing the effectiveness or payoff of a terrorism risk mitigation measure might initially seem to be a reasonably straightforward challenge. However, the effectiveness or cost-effectiveness of any terrorism risk mitigation initiative is inevitably dependent upon, and confounded by the way terrorists react to that measure…. Related closely to the issue of predicting the effectiveness or cost-effectiveness of risk mitigation measures is deciding how much our Nation should be willing to allocate to terrorism risk reduction, or how great a risk of terrorism we should be willing to accept. In reaching this judgment it must be recognized explicitly that resources allocated to reducing the risk of terrorism impose an economic cost on the Nation since they are unavailable for other needs. Thus, anti-terror initiatives represent other opportunities foregone and must be evaluated as such.” [Perhaps money allocated to homeland security could help the Nation more if it were used for something other than homeland security.]

Maybe risk can be salvaged as a way to allocate homeland security resources effectively. If you are in that camp, I think you will find the paper — and the questions it contains for the conference panels — intriguing and thoughtful.

The problems we have experienced trying to get homeland security risk assessments correct might also signal an opportunity to try something fundamentally different. Maybe we have traveled long enough down the risk assessment path.

It is a viable threat and you can say it isn't til you are blue in the face and it won't matter. I could make a shoe bomb that you would never notice until it blew up or was xrayed, it would take me about 30 minutes. The threat is there, until better testing procedures can be designed or deployed, these are the current steps taken to mitigate the threat.

I disagree with your assessment on the ability to transport. The results can be unpredictable, but the opportunity is there. You are ignoring the fact that it doesn't have to be mixed up on the plane, some liquids are stable enough to be transported. Even Nitrocellulose is a possibility because it is reasonably stable.

If a person is willing to blow themselves up I really don't think they would be overly concerned about a premature explosion if it happened. But that does bring up an excellent point.

These types of bombs are to unstable to check yet are not if in carry-on baggage?

No one said building bombs is a safe job. But I do think the people who would do so have enough training to do so and have detonation at a time of their choosing.