Apart from further snarling Washington's already tangled traffic, the nuclear summit here these two days will probably do no harm. That's because it won't do much of anything.

Forty-seven nations may be gathered, but the two countries everyone is most worried about, North Korea and Iran, are not here. The next two biggest worries are India and Pakistan, both nuclear powers and in a perpetual standoff with each other. They are here, but their nuclear standoff is not on the agenda. Neither is the issue of sanctions against Iran to discourage its nuclear ambitions. And two of this country's strongest allies, Great Britain and Israel, will be represented not by their top leaders, but by subordinates.

Oh, and by the way, no binding decisions are expected to be made. Defense Secretary Gates said today that the conference would bring "concerted international attention" to the issue of nuclear proliferation.

President Obama seems to like these kinds of big meetings, whether anything concrete comes out of them or not. One thinks of the Copenhagen climate change gathering. Nothing binding there.

Then there was the health care summit with congressional Republicans, who came prepared with arguments and ideas, none of which went anywhere. The president seems not to recognize the difference between activity and action. On second thought, maybe he does.

Brit Hume is the senior political analyst for Fox News Channel.