GWEN IFILL: For more on this, I'm joined by Feisal Istrabadi. He was Iraq's deputy ambassador to the United Nations 2004 to 2007. And David Ignatius, a foreign policy columnist for The Washington Post.

David, the president today in that interview that was published today described the fall of Ramadi as a tactical setback. Is it?

DAVID IGNATIUS, The Washington Post: I think it's more than that. I think it's a symbol that the strategy that the U.S. has been pursuing or encouraging Iraq to pursue for the last year — Mosul was overrun in June of last year — simply isn't working in reaching out to Sunnis, helping Sunnis push ISIS out of big cities like Mosul and now Ramadi, Fallujah, which is next to Baghdad.

Somehow, the administration has to find a way to help or push Abadi to reach out to the rest of his country. Otherwise, it looks to me as if these Sunni areas are gone.

GWEN IFILL: Do you think the problem lies with Abadi?

DAVID IGNATIUS: I think Abadi wants to do the right thing. He certainly tells U.S. officials often that he's trying to reach out to Sunnis, but, for a year, the U.S. has been trying to encourage Iraq to pass a law that would provide money and training and weapons for a Sunni national guard that could be effective in places like Ramadi, like Mosul, in turning back these Islamic fighters.

That legislation still has not been passed. And Abadi needs help and needs to be prodded. If the legislation isn't passed and the weapons and training don't come, there are no Sunni fighters.

GWEN IFILL: Feisal Istrabadi, is this a question of underestimating the strength of ISIS, not only by the United States, but also by the Iraqi government itself?

FEISAL ISTRABADI, Former Deputy UN Ambassador, Iraq: Well, that may very well be, although the stunning success that it had a year ago in taking Mosul in four hours should have focused all of our minds rather discretely.

I think that Mr. Ignatius is right, that there is not a — well, a year ago, the administration was right to say that it would only support the Iraqi government if political changes were made. It recognized then that political changes needed to be made on the ground in Iraq. Over that time, over the past year, it has not done enough, in my judgment, to insist upon that political accommodation being made and has focused too much on the military aspect of this engagement, and not enough on the political reforms that are needed, specifically things like reconciliation and some of the things that David Ignatius talked about a few moments ago.

GWEN IFILL: But I wonder — and I will start with you and I will ask David this as well — I wonder if this doesn't also speak to a disconnect in U.S. policy toward ISIS or toward defeating ISIS?

FEISAL ISTRABADI: It's not clear to me.

The spokesman said if there's a change of strategy, tell us what it is. A change of strategy suggests there is a strategy. I don't see a strategy that deals with — that concerns with dealing wit with ISIL overall. There is some sort of strategy for dealing with it in Iraq. I'm not sure there is one in Syria. And Libya is another problem altogether.

There doesn't — ISIL seems to have a strategy. They are metastasizing. But it isn't clear to me that the United States or indeed the Western alliance or the regional powers in fact have a strategy of confronting ISIL as such.

GWEN IFILL: David Ignatius, what about that?

DAVID IGNATIUS: Well, I think Mr. Istrabadi is right that the U.S. strategy has been that Iraq should come first. It's very hard to understand just what our strategy is in Syria, frankly, and on Iraq that this is Iraq's war, that the role of the United States is to help Iraq, to arm, train, support, provide air support, but this has to be Iraq's war.

I think President Obama, frankly, is reading the United States public correctly in judging that the country just isn't ready to send a big ground army back into Iraq.

GWEN IFILL: Even though there are 3,000 American advisers on the ground.

DAVID IGNATIUS: There are 3,000 American advisers, but there are limits on the American role. I wish that those advisers were leaning harder into the fight, because I think that would help embolden the Iraqi forces, on whom we are depending.

But we have to look at what's happened in the last week. I think the only judgment you can make is that what we're doing now isn't working. Important territory is being lost. And the president, if he wants to stick with his strategy, he has to be tougher about implementing it with Iraqis, with the American military that is providing the support. A whole series of things have to be stepped up, or we're going to see more reversals.

GWEN IFILL: Feisal Istrabadi, to what degree is Iran a complicating factor in all of this?

FEISAL ISTRABADI: Well, I mean, Iran is a complicating factor.

On the other hand, Iran is also engaged in the fight against ISIL for reasons of its own that include a desire not to see a reasonably friendly government in Baghdad falling. But it also includes its desire not to have ISIL's ideology spread in the region where it lives.

So, there is an opportunity for cooperation with Iran. ISIL is a common enemy. And I think we are at a point where the enemy of my enemy is close enough to being my friend at least.

GWEN IFILL: Is this kind of instability — and, of course, there's a lot of argument against the idea of the U.S. being friends with the enemy of their enemy — but does this kind of instability make it more difficult for the U.S. to accomplish other goals, like getting this nuclear deal?

DAVID IGNATIUS: Well, I think the U.S. has been careful not to go too far in attacking Iran's allies, in particular in attacking Hezbollah forces in Syria, which have been propping up the regime of Bashar al-Assad.

But the U.S. has to be careful. If our strategy depends on Sunnis doing the fighting to clear Mosul and Ramadi — and, as near as I can tell, that is the strategy — then you have to be careful that Sunnis don't perceive the U.S. to be operating arm in arm with Iran or with Iranian-backed Shiite militias that Abadi — Prime Minister Abadi is using in Iraq, so that, in effect, we're fronting for Iran.

That's a recipe for more Sunnis moving toward ISIS and away from the coalition.

GWEN IFILL: Feisal Istrabadi, it sounds like between a rock and a hard place once again.

FEISAL ISTRABADI: I'm afraid so.

And, of course, Mr. Ignatius is right on that last point. It has to be a very delicate balancing act. The fact is, I believe, that there is at least de facto cooperation between United States and Iran, at least in Iraq. And I think, if nothing else, it's a realization that they are a factor, they will be a factor. And on this one, at least, they're on the same side.

The militias are a problem, because the militias may well be driving people to the wrong side in places like Anbar. I'm not sure Abadi is so much using the militias as having them foisted on him. And that is a — that itself is a complicating factor.

GWEN IFILL: Feisal Istrabadi, David Ignatius, thank you both very much.

FEISAL ISTRABADI: Thank you.