Weird wording here:
Do we believe “the terrorists” will detonate an H-bomb…? That seems to me like a peculiar belief for someone to have. Also, who are “the terrorists” to you? Do you actually believe that there is something going on that is literally “the war on terror”? Al Qaeda, Afghanistan, Iraq, Islamic complaints, are religious/social/political conflicts, but terror itself is something else, as is the possibility of sudden attacks on civilians for any variety of reasons.
You don’t feel the attacks on 9–11-01 were the last ones? There have been many attacks since then. Until humans get over violence and labeling attackers as terrorists, there will continue to be “terrorist attacks.”
What do you mean by “checks and balances”? That term generally refers to the political balances designed into the American government to protect it from the kind of abuse that George W. Bush has perpetrated over the last eight years. If you mean measures like the new Homeland Security department and measures at borders and airports, those mainly serve to provide a new security industry, abuse civilians, win political points, and catch unskilled threats and violations. It seems pretty clear to me that a sufficiently intelligent and determined group could pull off a variant of the airline hijack kamikaze plan, or some other spectacular attack.
Now, there are also agencies with very intelligent and capable people whose purposes include detecting and preventing nuclear attacks like you mention. Apparently they have been pretty effective so far… but ultimately, I don’t think it’s possible to make a nuclear (or other horrific) attack entirely impossible. What’s called for, and what looks far more possible to me, is actually resolving the conflict, by listening to and meeting needs on all sides, and not just playing “us vs. them”. I think that relative peace will happen, and I hope it happens before any nuclear or other horrific attacks. But I’m not sure I’d even want to live in a world where Homeland Security can make building a complex machine in secrecy impossible.