Popularity polls can be interesting. But they don’t really provide much substance. For example, in the final RealClearPolitics.com average before the 2008 election, John McCain enjoyed a 52 percent approval rating. That, plus $4, will get the senator a mocha at Starbucks. It didn’t get him into the White House.

As President Barack Obama wrapped up his latest overseas tour, pollsters again touted his popularity. “Polls conducted in 11 Arab countries show that although approval of U.S. leadership remains generally low, ratings are up in 8 countries including Egypt,” Gallup reported before Obama headed to the Middle East.

He also enjoyed a series of warm welcomes on the second leg of his journey, in Europe, where – here they are again – polls show he’s far more popular than former President George W. Bush. Fair enough. Everyone likes to be liked. But can Obama translate this popularity into productivity?

Consider Afghanistan.

The battle to remove the Taliban from that country started in the fall of 2001, and supposedly enjoyed widespread support. NATO invoked, for the first time, Article 5 of its constitution, saying that the attack on the U.S. had amounted to an attack on all alliance members.

Two years later NATO formally took command of the mission in Afghanistan. Yet the military involvement has remained an overwhelmingly American action. A few months ago, Obama increased the American commitment to defeating the Taliban, adding some 21,000 troops to Afghanistan. Our European allies haven’t come close to matching that action.

A few months ago Britain pledged to add some 1,000 soldiers to the 8,300 already serving in Afghanistan. But the rest of Europe committed just 5,000 more (non-combatant troops at that), 3,000 of whom will deploy only until the country’s election in August.

Obama’s personal popularity doesn’t help the American cause unless he can use it to convince European political leaders to support the mission in Afghanistan. NATO needs to send more combat troops – with no restrictions on how, when and where they may be deployed. Right now, many European nations won’t allow their forces to deploy to combat zones. That must change.

The president should also encourage his European counterparts to sign off on America’s joint efforts with Pakistan to eliminate militant sanctuaries and Taliban and al Qaeda strongholds. These bases support the insurgents’ efforts in Afghanistan. It’s all part of the same fight – one the free world can’t afford to lose.

Meanwhile, Obama should insist that our European allies do more to help rein in Iran’s nuclear ambitions. Despite years of talks, Iran’s president still insists Israel should be, “wiped out from the map.” As if to make good on that pledge, Tehran is racing ahead with its nuclear enrichment and ballistic missile programs.

What good is popularity unless it helps convince Germany to join the U.S. in increasing sanctions on the rogue Iranian regime? Last year alone, German exports to Iran increased by 10 percent. Berlin became Iran’s largest trading partner even as it was leading the “EU three” talks supposedly aimed at preventing a nuclear Iran.

Germany can’t be both Iran’s trading buddy and its weapons denier. Obama should press the country to do the right thing and stop propping up Iran’s dangerous leadership.

High popularity ratings are helpful to any politician. But they should be a means to an end – not an end in and of themselves.

After two trips to Europe, Barack Obama clearly enjoys widespread popularity there. Now comes the difficult part: converting that political capital into policy successes. History will judge him on how effectively he does that, and it tends to be a harsher critic than any popularity poll.