MR. FRANK SESNOAnd thanks for joining us. I'm Frank Sesno of the George Washington University sitting in for Diane Rehm today. She's on vacation. Today is the first day of the Republican National Convention and we'll talk about that later this hour. But first, it has been a brutal and bloody few weeks in the United States and across the globe. France, once again, finding itself grieving after 84 people killed when an attacker plowed through -- plowed a truck through a crowd of revelers in Nice.

MR. FRANK SESNOJust hours after that, there was news out of Turkey, a coup attempt there, which ultimately failed, but not before more than 250 people lost their lives. A major crackdown is underway in Turkey, a key U.S. ally. So here to help us understand what happened in both places and what to make of these events in terms of U.S. security and later in the program, the political equation as the Republican Convention gets underway is Bruce Hoffman.

MR. FRANK SESNOHe's director of the Center for Security Studies at Georgetown and a senior fellow for the U.S. Military Academy's Combating Terrorism Center. Welcome, Bruce.

MR. BRUCE HOFFMANThank you.

SESNOThanks so much for coming in. Bruce, let's start with Turkey. What's the latest? What's happening there three days after this attempted coup?

HOFFMANWhat had initially been portrayed by as coup by roughly 50 army officers has expanded far beyond that in terms of retribution or identifying those culpable. Some 6,000 soldiers have been detained, nearly 3,000 judges have been removed from their jobs, some 8,000 police officers around the country have been removed from their posts, 30 regional governors have been dismissed and 50 senior civil servants have also been dismissed. So it's almost a whole self purge, really.

SESNOIs this an -- is there an indication or any evidence that all of these people who have been purged were actually complicit in the coup or are they being purged because this is a convenient time for the person who's in charge, Erdogan, in the country to assert even more control?

HOFFMANIt seems it's an accelerated or hyper version of the process that we expected to unfold after the constitutional referendum in October that would've further consolidated Erdogan's power. I mean, initially, reports were that this was a very limited number of renegade military officers. Obviously, it went beyond that. But the expansion of likely suspects has now achieved, I think, significant proportions so that it is a purge of any potential or possible opponent of the Erdogan regime.

SESNOAnd have key opponents of the regime, key players, been arrested?

HOFFMANNot that I've seen of members of political parties. In fact, all the political parties in Turkey were against the coup. This seems to be people in the civil service, in the judiciary, in the security services and the police whose loyalty at anyways being suspected or doubted.

SESNOWhy was everyone, including the Secretary of State John Kerry, in this country, so taken by surprise, so blindsided by this coup?

HOFFMANWell, it was a very interesting coup. I think it was a grass roots coup more than anything else and that also accounts for its failure. It was mostly majors and colonels, for example, who conspired very quietly and clandestinely and so the upper reaches of the Turkish general command didn't know about it and I think that's why it caught everybody by surprise.

SESNOWere you surprised by it? You cover -- you follow this stuff very closely and you know the degree of discontent, shall we say, that's been roiling Turkey.

HOFFMANWell, in one respect, it was almost a now or never. If there was going to be a coup, if there was going to be an attempt by the military to reassert the Kabbalist roots of the Turkish Republic, it was probably now was the last chance, especially, by the way, while the president was on vacation in Holland.

SESNOAlways a convenient time to launch a coup.

HOFFMANPrecisely.

SESNONow, Erdogan has also pointed fingers at a guy who lives in the United States in America of being behind this, Fethullah Gulen for the coup attempt. And he who -- he lives in Pennsylvania. He's usually, virtually reclusive. He did break that to come out and deny all this. Who is this man and is there any indication that he was part of this?

HOFFMANWell, I mean, Gulen himself has been a bete noire of Erdogan's for three years now, since they actually broke over a major corruption trial. He's been living in exile in the United States. Turkey has repeatedly branded him a terrorist and requested his extradition so the kind of rhetoric we're seeing from Ankara right now is not surprising. I'm sure there were Gulen supporters involved. I'm not necessarily sure that Gulen, in any sense, orchestrated this, at least, as being alleged.

HOFFMANGulen is almost like the Trotsky to Stalin in the 1930s and the 1940s, a scapegoat, someone who has definitely gotten under Erdogan's skin, who Erdogan does see as one of his main challengers. And obviously, he's being singled out as one of the individuals responsible. But as yet, there's no evidence one way or the other.

SESNOAnd it's been an irritant in U.S. -- in Turkey's relationship with the United States. In fact, there was a discussion that, you know, he should be extradited and the U.S. says, well, okay, file the right papers and we'll take a look at it. But the America connection is a very important one. Turkey is a key U.S. ally. It's a key NATO ally. The Incirlik air base is a U.S. air base from which anti-ISIS operations are taking place. The power was cut to that base.

SESNOThe Turkish commander to the base is one of those who's been arrested. So what are the security concerns or realities for America in all of this.

HOFFMANWell, last week, Joby Warrick had a fascinating article in The Washington Post, which shows how complex this situation is, where in essence that article argued that several high-ranking al-Qaeda officials or people sympathetic to al-Qaeda have been given sanctuary in Turkey. One of them, Rafai Taha was actually killed in April in a drone strike when he left Turkey and crossed the border into Syria. Mohammed Islambuli, whose brother killed President Sadat in 1980, who is the leader of the Islamic group in Egypt, has been given asylum in Turkey.

HOFFMANSo in some sense, there's a jihadi element that, interestingly, I think, also had been mobilized in part of the counter coup. There were reports, for instance, of hapless Turkish conscripts being beheaded on the bridges in Istanbul. On the jihadis own social media, they're crowing about the positive role that they played in backstopping the Erdogan government. So there's enormous complexity with charges being hurled on both sides of who's harboring terrorists.

SESNOSo you're the president of the United States or the next president of the United States and you're watching all this. What is your bottom line then as to what this means for U.S. security and the effort against ISIS and terrorism?

HOFFMANWell, access to Incirlik, the air base in Turkey, drives a lot of U.S. policy. It's one of the key NATO bases in any event, but especially in the war against ISIS, it's absolutely critical. Most of the air sorties are being flown by the United States out of Incirlik and preserving good relations to Turkey and continued access to the base has been paramount. We saw what happened during the coup when power was cut off and also, for a time, all U.S. flights were grounded. So the air campaign against ISIS stopped.

SESNOLet's turn to France now and the events that have taken place, terrible events that have taken place there over the last week and the broadening investigation in France as to what may have happened. 84 people killed, as we know, on Thursday by this 31-year-old Tunisian immigrant driving a 19 ton truck. What's the latest?

HOFFMANWell, I mean, there's more probing into Mohamed Bouhlel, the driver's background. I mean, apparently, as has not been surprising in recent months, we found out that he's from a somehow tortured personal life, marital problems, custody problems over his children, somehow found meaning and purpose in his existence by at least carrying out this attack in the service of ISIS goals, because ISIS, of course, has claimed him.

SESNOYeah, ISIS has claimed him, but did he claim ISIS?

HOFFMANHe didn't claim ISIS, but the latest report is that he texted a message before he began his attack to some conspirator asking for weapons and asking for help.

SESNOTo bring weapons, bring more weapons, right.

HOFFMANPrecisely. So this may not be the case of a lone individual motivated by intense frustration, idiosyncratic personal motives, just deciding to get in a truck and mow down people.

SESNOSecretary of State Kerry said brace yourself because these are the sorts of acts of a desperate movement. ISIS is losing territory and presumably it's lashing out. Is that how you read this?

HOFFMANNo, not at all. Over the past two years, ISIS has deliberately built up an independent external operations capability. It's on the (word?) where they have both built an infrastructure to support terrorist operations, direct command and control, but also built a process where they can reach out, radicalize individuals and attack their enemies in almost a two-pronged matter. On the one hand, directed ordered terrorist attacks, on the other hand, inspired motivated attacks by independents or would-be or wannabe terrorists who, almost overnight, are radicalized.

SESNOWhat about all this about all this territory they're losing and the money that they're losing and the clamp down that's affecting their leadership?

HOFFMANNo, all true. That's absolutely right. My only argument is that what we're seeing in Europe is part of a process that has been unfolding over the past two years, that it's not a flash in the pan and it's not a response to defeat. We have to look at this as part of an overall campaign plan.

SESNOAnd what is that part -- overall campaign plan look like or should it look like, in your view?

HOFFMANWell, the campaign plan, I think, firstly and foremost entails overwhelming the authorities, the law enforcement and security and intelligence securities of western countries with thousands of leads from individuals who may or may not have been radicalized and may or may not pose a threat causing them to be so distracted and preoccupied by, let's say, these low level actors that ISIS hopes the big attack can sneak under the radar and succeed.

SESNOWhen we come back, we're going to broaden the conversation to the convention hall, but very quickly, do you expect that these events around the world are going to really reverberate and echo through these political conventions? Does this change the narrative?

HOFFMANThey already have. I mean, the last two presidential elections, terrorism hardly figured at all. And since Paris and San Bernardino in the fall, they've been a prominent fixture of the primaries and then they will be of the presidential as well.

SESNODemanding answers, demanding specifics from candidate?

HOFFMANWell, I think generating fear and anxiety amongst publics, causing deep fissures in polities, which, of course, is the age-old stock and trade of terrorism. That's what terrorists are always trying to do.

SESNOAnd politics and political campaigns look for easy answers, quick soundbites, bumper stickers. This is not something that's going to fit that mold.

HOFFMANWell, from the terrorist's point of view, it thrust their agenda onto the political debate and terrorists thrive on attention. They believe that they can harness that for power, to intimidate, to cow their opponents into exceeding to their demands.

SESNOBruce Hoffman, you'll be with us. We'll be joined by two others. If you want to join our conversation, it's 1-800-433-8850 or you can email us at drshow@wamu.org. Stay with us. Our conversation on the world and it is a messy world, and politics which intensify this week as "The Diane Rehm Show" continues.