U.S. air strikes on Syria would face formidable obstacles

U.S. President Barack Obama delivers a statement from Martha's Vineyard, Massachusetts, during his vacation August 20, 2014. REUTERS/Kevin Lamarque

WASHINGTON (Reuters) - American forces face formidable challenges as President Barack Obama considers an air assault on Islamist fighters in Syria, including intelligence gaps on potential targets, concerns about Syria’s air defenses and fears that the militants may have anti-aircraft weapons, current and former U.S. officials say.

The Pentagon began preparing options for an assault on Islamic State fighters after the militants last week posted a gruesome video showing the beheading of American photojournalist James Foley. Deliberations by Obama’s national security team on expanding the campaign against Islamic State from Iraq into neighbouring Syria gathered pace in recent days, officials say.