The fact that a polynomial time algorithm can violate key properties of the system -- enabling double spending, preventing others from spending their money, killing the mining reward -- is fatal, at least from a cryptography standpoint. If it took half the users of Bitcoin to collude, that might be acceptable; but the fact that one user with lots of computing power can do this calls Bitcoin's value as a secure system into question.

Of course, the lack of a security definition for Bitcoin makes this point moot anyway.

That, in fact, was the judicial reasoning on the constitutionality of child pornography laws. At this point, though, I have my doubts that this sort of economic argument is valid; I doubt that the consumers of child pornography are paying for it in any way. After all, we are supposed to believe that the Internet has ruined the MPAA's and RIAA's business, and child pornography is obviously not subject to copyrights.

"Something must be done. This is something. Therefore, it must be done!"

I suspect that mass refusal to enter the body scanners would result in the use of metal detectors. The TSA is not going to punish more than a tiny minority of people, because they know that they are unpopular. They know that libertarian politicians want to ax their entire agency. They know that respected researchers like Bruce Schneier have nothing but bad things to say about their approach to security. They know that they are less popular than the IRS. Their actions now are about public relations, trying to keep the amount of negative press to a minimum.

I had a similar experience. I opted out, and then they noticed the line getting too long -- so they just let people through metal detectors. I was still waiting for my pat-down until I demanded that I be allowed through and accused them of punishing me for exercising my rights.

My experiences with the TSA's airport security have led me to conclude the following:

1. They hire the least intelligent people they can find. People who do not ask questions, because they lack the intelligence needed to do so.
2. They are terrified of any further resentment by the public. They are more concerned about their image than about keeping us safe (but we knew that anyway).

On the one hand, I would prefer if wars were always soldier-versus-soldier. On the other hand, I would rather see a robot on the battlefield making automatic decisions about what to attack than a bomb dropped from an airplane -- at least a robot can be programmed not to kill civilians or needlessly destroy civilian infrastructure (e.g. schools, hospitals).

Where I see a problem is with robots being programmed to recklessly kill -- a genocide could be committed rapidly by robots, which would require no indoctrination and would not refuse to target a particular group. I also see an issue akin to the problem with landmines, where robots might remain hidden, armed, and active long after a war ends. There is also the issue of robots recording or not recording their actions, which might be a concern during a war crimes trial (soldiers can testify that they were ordered to shoot children or deploy nerve gas; robots might not record such details).

Robots should find an empty field somewhere and self-destruct after some period of time without receiving commands. We do not want to wind up with the same situation we have with land mines -- dangerous leftovers from wars that ended decades ago. Imagine an autonomous robot getting lost during a war, only to get uncovered 10 years after the war ends and going on a rampage (say, killing every armed police officer it finds)...

If an infected application can affect other applications, it is an OS issue. Your infected web browser should not be able to read your GPG keys, but right now most GNU/Linux distros do nothing to stop that from happening.

Unless you bother to examine the public record of all Bitcoin transactions.

Except that you need to broadcast the transaction to the Bitcoin network, which must then confirm that the transaction is valid. What I said is that most people rely on another agent to complete their transactions for them -- because most people want fiat currency, not Bitcoin currency, and they usually do not want to wait for confirmations (nor do they want to accept payments without confirmations) or deal with an ever-fluctuating exchange rate.

Let's put it this way: try to use gold to buy a car, or even to buy something as simple as a single meal.

Bitcoin has never been anonymous. There is a public record of transactions. You have to rely on a separate mixing service, which almost nobody does.

Most important, though, is this: very few people actually want to use Bitcoin. Most view it as a way to make an electronic transfer of government-backed fiat currencies, so they rely on services that do the Bitcoin transfers for them and exchange Bitcoin currency for fiat currency. Those services are going to comply with the law and require things like identification. To put it another way, cash is anonymous too -- but large numbers of people use credit and debit cards, which are not anonymous.

Speaking as someone who has done exactly that...it is not really so bad, as long as you have time for it. The biggest problem was not with being on a train (it is far more pleasant to spend 4 days on a train than one hour on an airplane), but with delays caused by freight railroads prioritizing their traffic. If Amtrak were running on its own right-of-way rather than leasing, the journey would probably face far fewer delays, and the trains could run much faster (though not as fast as Japanese trains).

It is hard to talk about what makes "economic sense" here, since the passenger rail business was killed by competition from heavily subsidized alternatives: the interstate highway system, and airplanes. Had no federal money been spent promoting cars and airplanes -- had the government instead allowed competition between businesses determine how Americans travel -- passenger railroads would probably remain a viable business (but I doubt we would see high speed rail, for the same reasons that private Internet services are slower than the government-run services in other countries).

https://en.wikipedia.org/wiki/Apollo_mission

https://en.wikipedia.org/wiki/Interstate_highway_system

https://en.wikipedia.org/wiki/Panama_canal

https://en.wikipedia.org/wiki/Hoover_dam

...just to name a few. I guess if you just ignore the successes of the US government (except for your personal favorite), though, federal money would seem to be wasted on failure.

If we make exceptions for the blind, our next step might to make exceptions for the deaf, for libraries, for schoolchildren, for the poor, and then one day the movie studios might have to actually adapt to new technologies instead of trying to kill them.

Opinions are not facts, so they cannot be "wrong." The view itself is not at all unprecendented or even unusual.

What I think is not really the issue here. My only point is that there are people who have no issue with homosexuality but who still oppose gay marriage.

No, it is just a matter of defining the purpose of marriage. Just because you think marriage is only about love does not mean that everyone else does, nor that everyone else should.

As we all know, calling people who disagree with you "scum" is a productive activity. You're really going to make strides in convincing people to support gay marriage with that approach -- keep up the good work!