WASHINGTON - The center of gravity in the U.S. war against Islamic extremism is moving east, from Iraq to Afghanistan, and the first Minnesota congressman to personally chart the new course is Rep. John Kline, a Lakeville Republican who was recently named to the House Intelligence Committee.

Kline, just back from a secret trip to Afghanistan, gave a sober assessment Monday of the task ahead. "You've got a tougher opponent in Afghanistan than we had in Iraq," Kline said in an interview with the Star Tribune, his first upon returning from a congressional tour that included Turkey, Israel, the West Bank and Pakistan.

The trip comes as President Obama has announced plans to shift troops out of Iraq and beef up U.S. forces in Afghanistan, where U.S. and international troops have been battling Al-Qaida and Taliban fighters since the 9/11 attacks.

In terms of both mountainous terrain and the enemy's motivation, training and leadership, Kline, a retired Marine colonel, said the tactical situation in Afghanistan will be much more challenging for U.S. troops.

"They're very tough fighters," he said of the Taliban. "I don't want to be dismissive of the insurgents in Iraq, but they're different."

Kline, a former military aide to Presidents Carter and Reagan -- and an increasingly influential GOP voice on military affairs -- could also be a bellwether of Republican support for Obama's first big military venture. While Kline and other Republicans have raised questions about the Obama administration's proposed cuts to major weapons systems, Kline thinks the GOP will coalesce around the new administration's strategy in Afghanistan.

"We conveyed the same message to the people of Afghanistan, Pakistan and Turkey," he said. "We're all supportive of what the president is trying to do with his new regional strategy."

Kline was a staunch supporter of President George W. Bush's invasion of Iraq, which Obama saw as a distraction from the hunt for Osama Bin Laden and the rest of Al-Qaida's leadership.

Obama called the Taliban "resurgent" earlier this month in asking Congress for another $83.4 billion to fund the wars in Iraq and Afghanistan through the end of September.

Some anti-war Democrats have argued that instead of attempting to find a military solution in Afghanistan, Obama should focus on promoting reconciliation, economic development and humanitarian aid. Some Republicans, meanwhile, accuse Obama of shortchanging the war on terror through his budget.

While Defense Secretary Robert Gates has recommended slashing a number of expensive weapons programs such as the F-22 jet fighter, Obama's defense budget would increase spending by 4 percent over the current year.

Last month, Obama announced that the United States plans to withdraw most of its troops from Iraq by the end of August 2010, leaving a residual force of between 35,000 and 50,000 troops until the end of 2011. There are about 142,000 U.S. troops in Iraq now.

Meanwhile, Obama has ordered the deployment of 17,000 troops to fight the Taliban, and 4,000 more to train Afghan troops.

Kline noted that the build-up still falls short of the 30,000 additional troops requested by Gen. David McKiernan and other top military commanders in Afghanistan. But, he said, the additional troops will be welcomed by tribal leaders he met with in Afghanistan.

A greater international presence would also be welcome, Kline said, along with the greater cooperation of Pakistan, which has been a refuge for Al-Qaida and has seen a spike in terrorist attacks, as well. "It's very important that we be heavily engaged with Pakistan, as well as Afghanistan."