In Afghanistan you are not rebuilding, you are building. There is very limited infrastructure and extreme terrain, with deserts in the south and mountains so high in some areas that helicopters don't even fly well at a certain altitude because the air becomes so thin. The country has a serious problem of illiteracy, especially after so many years of war and Taliban rule.

We cleared many of their towns and cities and rural areas of al-Qaida Iraq and other insurgents.

The job of the leader is to get the big ideas right.

I am neither a pessimist nor an optimist. I am a realist, and the reality in Iraq is that it has been very hard and it continues to be hard.

People often ask, why aren't you reading about what it is you're working on right now? And the truth is, you only get three pages a night before your eyelids close.

There has, indeed, been very substantial progress in Iraq over the past year - violence is down by 80 percent, civilian deaths by about the same, and so on.

Items of interest will be located, identified, monitored, and remotely controlled through technologies such as radio-frequency identification, sensor networks, tiny embedded servers, and energy harvesters - all connected to the next-generation internet using abundant, low-cost, and high-power computing.