George Bush and Mexico's President Vicente Fox have a vibrant friendship. Their personal chemistry, which will be on display again this week during Mr. Fox's state visit to Washington, opens a path for significant improvement in a crucial hemispheric relationship.
Alas, it's not a path either leader can gallop down. The issues confronting the two countries demand careful, step-by-step progress.
Take issue No. 1: immigration. A joint task force has been working on this question for months. There was some hope this week's Fox-Bush summit would yield a major policy announcement regarding an expanded guest-worker program or some other way of dealing with the flow of illegal economic migrants from Mexico.
But in a pragmatic shift away from his usual robust optimism, Fox recently acknowledged that comprehensive immigration reform could take four to six years. That's an honest assessment of the project's prospects in the US political system. There's little support in Washington for any massive legalization or amnesty program for illegal immigrants. And for good reason. Such approaches just tend to exacerbate the problem.
But more thoughtful policies, including schemes that would allow greater numbers of Mexicans to "earn" legal status in the US, are worth exploring. Those who have stable employment, who are paying taxes and keeping out of trouble, would have a chance to become legal US residents.
On the Mexican side of the border, critical needs include a crackdown on the smuggling rings that exploit migrants, often leading to tragedy, and, as always, economic development in those regions that are home to most migrants.
Fox has shown a readiness to work with the US on law-enforcement issues, whether migrant smuggling or drug trafficking. He has also been a tireless advocate for economic development - seeking foreign investment and offering Mexicans "micro loans" to encourage the creation of small businesses.
His momentum, however, has been sapped by a sluggish world economy and a Mexican political system still very resistant to the extensive changes Fox has talked about.
But constructive change remains in the air. And the Washington meeting could bring it a little closer.