I think it's clear that these stunning advances of Isis in Iraq and Syria is certainly ringing alarm bells here in Washington.
There's a recognition that Isis is a ruthless enemy, that it has access to tens of millions of dollars and potentially continuing revenue through oil resources, and that it might also want to make a global statement of its ambitions.
You throw into the mix the fact that there may be other al-Qaida affiliates, rivals to Isis that are seeking to show their continuing relevance and credibility on the Jihadist stage and it's pretty clear why the Department of Homeland Security are really very concerned tonight.
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