That's rather defeatist. I'd say humanity doesn't have a chance of surviving if it doesn't figure out how to address the concerns of smart, disgruntled people.
Keeping them in check just delays the inevitable meltdown.
I'd say smart, disgruntled people aren't as smart as they think they are.
The societal problem is convincing everyone that they're a genius. When life hands them less than the best and they have to overcome it, they just get disgruntled, because "they're too smart" to deal with it.
Parents, remind your children that there's always going to be someone smarter/faster/stronger/etc than them, and that they should focus on doing as well as they can with the circumstances they're given. There's more good in being the best you can be than there is in being the best; for a lucky few, those things are identical, but for the rest of us they aren't.
> there's always going to be someone smarter/faster/stronger/etc than them
However in this country (the US) the gaps are wider and the deck is stacked more than in any other industrialized nation in pretty much every category.
Why don't we hear more about people flying planes into buildings in China? Or students (or even teachers!) losing it and shooting up their schools?
Is it just that they have better control of their media (so we don't hear about it), better control of the people (so they don't get a chance to do it), or something else?
By the way, there were also some incidence of pupils shooting up their schools in recent years in Germany. I guess you are just much more exposed to American incidents than to the rest of the world. (E.g. have you heard of the whole ugly neo-nazi stuff in east Germany in the 90ies? It still goes on, though at a much lower level of intensity. It's quite hard to find English language sources on the anti-asylum-seekers riots in Hoyerswerda in 1991 but http://www.jstor.org/pss/4146935 is on.)
There have been smart, disgruntled people forever. On the whole, I think they're less violent and therefore less dangerous than dumb, disgruntled people.
In terms of death toll, I'd probably disagree. It seems that 20 men from the upper classes (on horseback, armed and trained to use weapons) could destroy an 11th-century town of 1000-3000 inhabitants (although suffering heavy losses on their end) if they were so inclined. A powerful nobleman could assemble the knights.
In terms of impact, you're probably right. I think it's likely that 9/11 is the first news story to have reached half the world's population in a few hours. However, there are pre-modern events that rival it in terms of potential impact. I can't think of any from the 11th century, but the Defenestration of Prague comes to mind, as would the Gunpowder Plot had it succeeded.
If the Gunpowder Plot had succeeded, it wouldn't have been the destruction of parliament that would have been the issue, it would have likely been a full out campaign to kill every catholic in Briton by the most gruesome methods possible. The public reaction to the Gunpowder Plot was very 9/11 in terms of public opinion against the Catholics. In fact the Gunpowder Plot likely delayed the Catholic Emancipation by potentially two-centuries and increased intolerance towards Catholics quite dramatically.
Honestly if the Gunpowder Plot had succeeded, I have little doubt it would have turned into a massacre of Catholics in Briton and likely devolved into a full out war. Ireland would have received a full massacre for the guerilla war it had waged against Briton, and Spain would have likely come under full attack for supporting the Irish Catholics during that time.
It would be hard to see any result that isn't total war for a successful bombing. Ironically the plot was the worst thing to happen to Catholics but simultaneously the best outcome for the situation.
if the "smart, disgruntled" were so smart, they would figure out how to get what they want so as to be no longer disgruntled.
getting frustrated with life and throwing your hands up isn't smart.
Keeping them in check just delays the inevitable meltdown.