There is a war on terror. Terror is a legitimate threat. It is a threat that comes from al Qaeda and those organizations that have morphed off of al Qaeda, but there are other interests we have beyond merely... [etc]
You can hear it out of his own mouth here. The latest in the series of feeble arguments for why the phrase 'war on terror' is to be, er, shelved (before being used again and shelved again and used again) is, in effect, that it doesn't tell you everything about all aspects of all the situations in which terrorism may be occurring. As if any phrase for anything ever did that. Anyway, FKATWOT 19.
Incidentally, here is something the President said in Prague:
So, finally, we must ensure that terrorists never acquire a nuclear weapon. This is the most immediate and extreme threat to global security. One terrorist with one nuclear weapon could unleash massive destruction. Al Qaeda has said it seeks a bomb and that it would have no problem with using it. And we know that there is unsecured nuclear material across the globe. To protect our people, we must act with a sense of purpose without delay.
An 'extreme threat to global security' doesn't seem too extravagant a way of describing the possibility of a nuke being used by terrorists against a major city somewhere. Is it really appropriate to treat this threat as merely a matter of criminal justice and not also as one of national defence? Prepared within some countries against other countries, the latter, the target countries, are certainly not obliged to overlook the 'war-like' character of such a threat.