What was said: Almost nothing. McCain advisor Randy Scheunemann has used al Qaeda’s gains after the U.S. withdrawal from Somalia as a cautionary tale for Iraq, an interesting choice of example because McCain strongly supported the withdrawal. Obama’s advisors say he wants to “recalibrate” the U.S. approach to Somalia, but it’s unknown what that might entail.

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The Global Food Crisis

The issue: Caused by a perfect storm of economic factors including restrictive trade barriers, rising fuel prices, and increased demand from China and India, as well as poor harvests, food prices rose to record highs last spring and summer, threatening to push hundreds of millions around the world below the poverty line. Food riots broke out in Egypt, Indonesia, Haiti, and elsewhere. Food prices have decreased somewhat along with those of other commodities in recent months, but experts worry these decreases could actually exacerbate the problem as farmers cut back their harvests and rich countries focus on their own economic woes.

Why it matters: Along with China, the United States is one of the world’s primary food suppliers. It is the largest exporter of wheat, corn, and soybeans. So when the United States pumps billions into agricultural boondoggles like corn-based ethanol, it can cause significant fluctuations in global food prices. Somalia and Pakistan ought to be clear enough examples of why political instability—to which rising food prices are contributing—can make the world a more dangerous place.

What was said: The senator from Illinois is a major supporter of ethanol subsidies, a stance that has drawn repeated attacks from McCain. These attacks seem to be more motivated by McCain’s anti-pork principles than concern over food prices, however. Obama continues to support the subsidies but stresses that they are a “transitional technology” and that the United States should be “mindful” of the effect they have on food prices.

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Illegal Immigration

The issue: Considering how important the issue of immigration was in the Republican primary—a backlash on the right that sometimes veered into outright xenophobia very nearly cost McCain the nomination—its disappearance during the general election has been remarkable. Although immigration into the United States has slowed in recent years, a consequence of the slumping U.S. economy, the population of undocumented immigrants remains at an all-time high of nearly 12 million. Living in constant fear of deportation, illegal immigrants are prone to mistreatment by employers and lack access to basic social services. The United States’ porous southern border has also led to an increase in violent crime and drug trafficking on both sides of the Rio Grande.

Why it matters: You don’t have to be Lou Dobbs to see a problem with the United States not enforcing the laws on its own books. With little action to tackle the problem on the federal level, state and local law enforcement agencies are taking the matter into their own hands, resulting in the diversion of resources and inconsistent enforcement. There’s bipartisan support for comprehensive reform that would combine tougher border enforcement with a pathway to citizenship for illegal immigrants who already live in the United States, but some skill will be required for the next president to cut through the extremist demagoguery and convince skeptical voters.

What was said: McCain’s immigration stance has to be counted as the biggest “flip-flop” of his presidential run. The maverick Republican who joined with Democrats to support comprehensive immigration reform has shifted to a “secure the borders first” policy. Obama continues to support reform but has toughened his tone to emphasize that immigrants must “get right with the law.” Given that the moderate stance of both candidates is out of touch with a significant portion of the electorate, they seem to have both decided to downplay the issue. It hasn’t come up in any of their debates.