FACTBOX - Obama lays out policy on Iraq and national security

(Reuters) - U.S. presidential candidate Barack Obama on Tuesday said the United States must end its "single-minded" focus on Iraq, as he called for a broad revamping of the national security approach.

In a speech in Washington, the first-term Democratic senator from Illinois, who faces Republican John McCain in the November 4 election, laid out his policies on issues from Iraq and Iran to Afghanistan and Africa.

Here are some of the topics he covered:

IRAQ

Obama said the United States must have a serious debate about Iraq's "dominance of our foreign policy" and he underscored his call to remove U.S. combat troops from Iraq within 16 months.

"This war distracts us from every threat that we face and so many opportunities we could seize," he said. "By any measure, our single-minded and open-ended focus on Iraq is not a sound strategy for keeping America safe."

IRAN

Obama said that preventing Iran from acquiring a nuclear weapon was a vital American interest and pledged to use all tools to prevent that from happening.

"I will use all elements of American power to pressure the Iranian regime, starting with aggressive, principled and direct diplomacy -- diplomacy backed with strong sanctions and without preconditions," he said.