Tony Blinken, President Obama's deputy national security advisor, was outlining administration policy in the Middle East. "We're not going to fall into their trap of sending hundreds of thousands of Americans back," he told Fox News.The question hanging over Washington now is: How can that trap be avoided?The president has set out two clear principles. The first is to "degrade and ultimately destroy ISIL," the extreme jihadist movement also known as ISIS and Islamic State that now occupies large swaths of Iraq and Syria.