As Barack Obama is due to visit Saudi Arabia on March 28, the issue of U.S.-Saudi relations was highlighted again. President Obama's visit indicates that U.S.-Saudi differences, big as they are, should not be exaggerated, and they do in fact have reasons to embrace each other.

The recent Saudi anger toward the United States, marked by its refusal to accept the two-year non-permanent membership of the UN Security Council, actually reflected its long-accumulated dissatisfaction with the U.S. policies across various Middle East issues. Though Obama's sincerity of improving relations with the Saudis should not be doubted, that what he can really do remains limited. The change in the U.S. policy is of a structural and strategic nature, rather than of a tactical one.

Saudi Arabia regards toppling down the Bashar Assad regime as its vital interest since Assad is allies with Iran, a major regional rival of Saudi Arabia. In addition, Saudi Arabia strongly expects the United States to directly bomb Assad's regime. It also expects the United States will take a tough stance against Iran or even bomb it just to eliminate Iran's nuclear facilities. Saudi Arabia believes that a neighbor holding nuclear potential will pose a major threat to its national security.

It is true that the United States shares some of the interests and concerns with Saudi Arabia in the abovementioned areas. Yet it is highly unlikely that the United States will do as Saudi Arabia requires. It seems that the United States is not ready to invest more strategic resources in the Middle East. A single presidential visit by no way can pacify the Saudi anger.

In 2014, the U.S. budget deficit will reach US$18 trillion, 20 percent more than its annual GDP. Within this context, the United States can neither be financially ready nor determined to once again take military action in the region. The decade-long quagmire of the Afghanistan and Iraq wars not only exhausted U.S. resources, but also undermined the U.S. willingness to take in military actions.

Not to say, the United States regards the Asia-Pacific, instead of the Middle East, as much more important in its overall global strategy, and is shifting its resources towards that region. Rising tensions between the West and Russia -- on the Ukraine issue -- are also attracting U.S. strategic resources. The United States is certainly much busier than Saudi Arabia assumes.