The saying used to be that politics stops at the water's edge. Apparently that was before the 24-hour news cycle and the permanent campaign.

Republicans say they plan to keep up an aggressive rapid-response operation aimed at Barack Obama while he visits Iraq, Afghanistan, Israel and western Europe this week, hoping to counter the massive press coverage Obama's trip will generate. Foreign policy is one of the few areas where polls show John McCain has an edge with voters, and the GOP has no intention of letting Obama use the trip to catch up.

In fact, the Republican push-back has already started, even before Obama leaves. Early Thursday, McCain foreign policy advisor Randy Scheunemann sent reporters a memo titled "Barack Obama vs. the Facts," accusing Obama of making his mind up on the Middle East without hearing from the military first. "This week, Barack Obama announced his strategy for Iraq and Afghanistan," Scheunemann wrote. "He did this before visiting Iraq for the first time in well over 900 days, before ever visiting Afghanistan, and before meeting with our commanders on the ground." Marc Ambinder reports that a sneering documentary will be on its way soon, too.

Aides to the McCain campaign and the Republican National Committee say they're just following the new rules Obama and the Democratic National Committee set on McCain's own foreign trips earlier this year. The decision to go after Obama while he's out of the country was "not exactly controversial," McCain senior advisor Mark Salter told Salon. "When [McCain] was in Iraq, Democrats attacked him. Same for Europe, Canada, Colombia and Mexico." And they've already got the research to back it up, with a memo citing 10 different cases of Obama or the DNC hitting McCain for what he said while overseas earlier in the campaign. (In another departure from past history, both Obama and McCain are using their campaign funds to pay for some of their foreign travel. Obama's time in Iraq and Afghanistan will be an official congressional trip, but the rest is a campaign event, as was McCain's Latin America visit.)

Considering how much buzz Obama's trip is already getting, McCain aides don't think they have much choice. All three network anchors will fly along, meaning this little jaunt will probably be generating wall-to-wall TV segments and plenty of newspaper stories. With the cost of the airfare alone for press traveling with the campaign rumored to be around $15,000, any news organization who's sending someone will probably want a lot of material out of the trip to justify the cost. (Salon isn't going.) So even with a full GOP attack operation going on, McCain risks being swallowed in a tide of good press for Obama. If Republicans can squeeze a few talking points into news clips featuring hundreds of thousands watching Obama in Berlin, they'll probably call that a win.