Seymour M. Hersh makes a controversial claim in the LRB:
A former senior adviser to the Joint Chiefs told me that the document was an ‘all-source’ appraisal, drawing on information from signals, satellite and human intelligence, and took a dim view of the Obama administration’s insistence on continuing to finance and arm the so-called moderate rebel groups. By then, the CIA had been conspiring for more than a year with allies in the UK, Saudi Arabia and Qatar to ship guns and goods – to be used for the overthrow of Assad – from Libya, via Turkey, into Syria. The new intelligence estimate singled out Turkey as a major impediment to Obama’s Syria policy. The document showed, the adviser said, ‘that what was started as a covert US programme to arm and support the moderate rebels fighting Assad had been co-opted by Turkey, and had morphed into an across-the-board technical, arms and logistical programme for all of the opposition, including Jabhat al-Nusra and Islamic State. The so-called moderates had evaporated and the Free Syrian Army was a rump group stationed at an airbase in Turkey.’ The assessment was bleak: there was no viable ‘moderate’ opposition to Assad, and the US was arming extremists.
Lieutenant General Michael Flynn, director of the DIA between 2012 and 2014, confirmed that his agency had sent a constant stream of classified warnings to the civilian leadership about the dire consequences of toppling Assad. The jihadists, he said, were in control of the opposition. Turkey wasn’t doing enough to stop the smuggling of foreign fighters and weapons across the border. ‘If the American public saw the intelligence we were producing daily, at the most sensitive level, they would go ballistic,’ Flynn told me. ‘We understood Isis’s long-term strategy and its campaign plans, and we also discussed the fact that Turkey was looking the other way when it came to the growth of the Islamic State inside Syria.’ The DIA’s reporting, he said, ‘got enormous pushback’ from the Obama administration. ‘I felt that they did not want to hear the truth.’
‘Our policy of arming the opposition to Assad was unsuccessful and actually having a negative impact,’ the former JCS adviser said. ‘The Joint Chiefs believed that Assad should not be replaced by fundamentalists. The administration’s policy was contradictory. They wanted Assad to go but the opposition was dominated by extremists. So who was going to replace him? To say Assad’s got to go is fine, but if you follow that through – therefore anyone is better. It’s the “anybody else is better” issue that the JCS had with Obama’s policy.’ The Joint Chiefs felt that a direct challenge to Obama’s policy would have ‘had a zero chance of success’. So in the autumn of 2013 they decided to take steps against the extremists without going through political channels, by providing US intelligence to the militaries of other nations, on the understanding that it would be passed on to the Syrian army and used against the common enemy, Jabhat al-Nusra and Islamic State.
Germany, Israel and Russia were in contact with the Syrian army, and able to exercise some influence over Assad’s decisions – it was through them that US intelligence would be shared.