US President George W Bush has arrived in East Asia for talks with regional leaders and to attend the annual Apec summit of Asian and Pacific countries.
Bush used the refuelling stop to hit back at his critics
His eight-day journey will take in Japan, South Korea, China and Mongolia.
A possible bird flu pandemic, niggling trade issues and promoting democracy and free markets are expected to top his agenda.
But first Mr Bush hit back at his Iraq critics while on a refuelling stop at a military airbase in Alaska.
He told troops at Elmendorf base that Democrats who once agreed that former Iraqi President Saddam Hussein was a dangerous threat and backed the White House administration over the use of force in Iraq were "now rewriting the past".
"They're playing politics with this issue, and they are sending mixed signals to our troops and the enemy. That is irresponsible," Mr Bush said.
His plane, Air Force One then headed for Japan on the first leg of the tour.
On Wednesday, Mr Bush is due to meet with Japanese Prime Minister Junichiro Koizumi and give what his aides call an important speech.
In South Korea, his next stop, he will join the other 20 Apec member states, hoping for greater co-operation on trade and security as well as plans to counter a possible bird flu pandemic.
Analysts predict Mr Bush will have to tread carefully when he visits China to discuss the delicate issues of trade and currency revaluation, as well as human rights and Taiwan.
He is expected to get a warmer reception in Mongolia, an infant Asian democracy which has sent troops to Iraq.
The BBC's Adam Brookes, who is travelling with Mr Bush, says much is expected to be made of what the Bush administration calls its message of freedom - a belief that democracy and free markets are the solution to extremism and instability.
White House officials have played down expectations of the trip. "He's not looking for specific deliverables or specific outcomes," National Security Adviser Stephen Hadley said.
But the success of the trip will be measured in terms of how far Mr Bush can persuade Asian countries that his vision of the world is relevant, our correspondent adds.
The trip comes at a time when Mr Bush is suffering from a number of domestic problems, and his standing worldwide is not what it was.
Asian leaders will be watching, listening and assessing to see where US global leadership is likely to take them, our correspondent says.