Obama Aide Says Iran's Leaders Are Feeling the Strain of Sanctions.

WASHINGTON -- A day after the United States imposed fresh sanctions on Iran over its nuclear program, President Obama's national security adviser argued Tuesday that the administration's pressure campaign had left Iran's leaders economically strained, diplomatically isolated and rent by internal divisions. The official, Thomas E. Donilon, predicted that the next blow to Iran would come with the fall of its major regional ally, President Bashar al-Assad of Syria, who is himself increasingly isolated as he battles a popular uprising. [ABSTRACT FROM PUBLISHER]