For some, the intentional vagueness of the alert is almost as frightening as the fact that there's an alert. As Scott Shane sharply notes , what should travelers do? "Be aware" of your surroundings at all times. Also, "take appropriate safety measures."

According to a vague public alert issued urgently Sunday, there is maybe a possible al Qaeda terrorist threat in Europe somewhere involving possibly, but they're not sure, airplanes, subways, ships or railroads. Or also other unspecified elements of tourist infrastructure. And it could be large-scale.

If you're traveling somewhere, the Obama administration's State Department advises, be careful about something.

...status things issued during the Bush administration. Quick, what level are we now? How bad is orange vs yellow?

According to U.S. and European officials, a boost in buzz among terrorists and a captive trainee in recent months suggest something might be afoot somewhere between Iceland and Norway and Ukraine and Azerbaijan. It could be as large as 9/11. Or larger. Or maybe not.

Meanwhile, thanks to Greg Pollowitz over at NRO, we get this dose of skepticism from Germany.

A State Department travel warning, you should know, is more serious than a travel alert. Thus, a travel warning suggests Americans refrain from journeys into areas of Sudan consumed by civil war, which seems like a good idea even for adventure seekers.

Travel alerts in recent months have advised extra care traveling to India and Bolivia. Now, Europe.

Coming after days of meetings within and without the White House, Sunday's alert, however, merely narrowed the danger zone down to four dozen countries covering some 4 million square miles of the planet's surface, an area slightly larger than the entire United States.

A White House spokesman said, "We need to do everything possible to disrupt this plot and protect the American people.” (So, there is a specific plot?)

There could be a faint hope that by announcing we know something is up, it might deter some wimpy terrorists, like shouting in the dark, "I know you're there!" Even if you don't really know. Or maybe we really do know possible targets within that vast area, but we don't want them to know how much we do know because inside informants are still probing. Or maybe....

It's a genuine political quandary for any administration in an open society. Imagine for a moment if, because the potential targets are so nondescript and the area so vast and the time frame so vague that no alert gets issued. But, then, some kind of attack does occur.

Do you think that might make a major story in the news media? "U.S. Govt. Knew of Attack, Failed to Alert Public."

All of which suggests it's time to alert Americans to prepare themselves for numerous CYA travel alerts in coming months and years. Not every travel alert will be succeeded by a terrorist incident. But for the sake of public safety -- and political safety -- every terrorist attack had better be preceeded by a travel alert.

-- Andrew Malcolm

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