9/11, remembered; al Qaeda, still dangerous; Syrian ‘Roundup’; The military’s new tooth mics; And a bit more.

A hallowed morning at the Pentagon: Defense Secretary Jim Mattis and Vice Chairman of the Joint Chiefs of Staff Gen. Paul Selva are speaking publicly on the 17th anniversary of the 9/11 attacks at the Pentagon Memorial — and in the presence of distinguished guest Vice President Mike Pence.

Some of Mattis’s remarks: “[T]his morning we commit ourselves to remembering and honoring the lives that might have been: we keep faith with the innocent who perished; we take solace their deaths were not in vain, for in their passing they empowered us forever; and we remember that hatred, disguised in false religious garb to murder innocents, will not prevail… We remember the bravery and sacrifice of those who fell here in America, and then on far-flung battlefields. We salute the Soldiers, Sailors, Airmen, Marines and Coastguardsmen who 'nailed our colors to the mast,' giving their last full measure of devotion, declaring proudly that Americans do not scare. And we followed to the ends of the earth those who sought to break our spirit.”

A bit of Gen. Selva’s thoughts: "None anticipated an attack on the nation that day, but as we gather here 17 years later, we know September 11, 2001, will always stand apart from other days. It is a day that our nation and our families will never forget. Terrorists attacked this nation because of what we believe in, and the innocents died because of what they represented: freedom and liberty...The two million Soldiers, Sailors, Airmen, Marines, and Coast Guardsmen who wear the uniform of this nation carry the spirit of that legacy inside them as they serve courageously and selflessly around the world. The majority of them joined after 9/11 because of 9/11..."

Catch the VP, SecDef and Vice Chief’s full remarks from the Pentagon this morning over at DVIDS, here.

The first thing on POTUS45’s public mind this morning: Allegations of collusion with Russia, according to this a.m. tweet.

From Defense One

The Military Now Has Tooth Mics For Invisible, Hands-Free Radio Calls // Patrick Tucker: The future of battlefield communications is resting comfortably near your back gums.

Stuck Fighting the Last War // Hassan Hassan, Tahrir Institute for Middle East Policy: It’s 2011—not 2001—that defines the challenge facing the United States and its allies in combatting jihadism.

How to Dampen Escalation Risks As Cyber-Attack Rules Loosen // Erica D. Borghard and Shawn W. Lonergan, Council on Foreign Relations: Create standing rules of engagement and maintain the dual-hatted NSA/CyberCommand.

Republicans Balk at Democrats’ Pledge to Snub Hackers // Natasha Bertrand, The Atlantic: So far, only House Democrats have chosen to hold themselves publicly accountable for how they plan to handle any stolen documents that come their way.

Welcome, Class of 2022: Last of the Pre-9/11 Cohort // Brent Colburn, Princeton University: Your arrival reminds us all to do more to connect America’s citizens to their country’s wars, and its civilians to its veterans.

Welcome to this Tuesday edition of The D Brief  by Ben Watson and Bradley Peniston. And if you find this useful, consider forwarding it to a friend or colleague. On this day in 1864, Union Gen. William Sherman and Confederate Gen. John Bell Hood declared a 10-day truce so civilians could leave Atlanta before Sherman’s troops lit it up in a legendary offensive.

A suicide bomber in eastern Afghanistan has killed more than two dozen people. “Officials and elders said Tuesday’s attack targeted a gathering to protest against a police commander, adding that hundreds of people were present when the blast happened. The blast dispersed the crowd, but more people gathered after the explosion to continue the protest.”
The Taliban say it wasn’t them, and told Reuters they look forward to talking to U.S. officials again about possible prospects for peace in the 17-plus-year conflict.
Elsewhere in the country, Reuters reports, “In the northern province of Sar-e Pul, hundreds of armed men assembled to boost the city’s defenses as security forces fought to push the Taliban back from the city center.” Elsewhere still, “Two air strikes in Baghlan province on Tuesday followed six the day before and American advisers were on the ground supporting Afghan troops.” A bit more, here.

On war, the environment and the “graveyard of empires.” More Afghans in the western part of the country have been displaced by drought than war, the UN says in a new report.
The quick read: “A total of 275,000 people have been displaced by drought in western Afghanistan — 52,000 more than the number uprooted by conflict this year — with over two million threatened by the effects of water shortages,” Reuters writes off the report. There are more ominous numbers to consider if you’d like to continue reading, here.

In eastern Syria, the U.S. military and its partnered forces have begun “phase three” of Operation Roundup: the mission to clear remaining ISIS fighters from northeastern Syria, along the Middle Euphrates River Valley and toward the Syria-Iraq border.
Expect cross-border air and artillery strikes, U.S. Central Command announced in a statement as the op kicked off.
Reminder: “Phase one successfully cleared ISIS near Baghuz in northeastern Syria May 15,” CENTCOM said. “Phase two cleared ISIS from Dashisha, Syria July 20. Shaping operations for phase three began Aug. 4.”
One key focus of phase three: Hajin, Syria — the “last IS-held pocket in Syria,” according to Kurdistan24 news. The U.S.-backed Syrian Democratic Forces told Kurdistan24 that they “will attack Hajin from four axes, aiming at liberating the remaining areas of Sousah and Sha’aafah on the Euphrates River.”
Afterward, expect the SDF to head to the “Dayr Az Zawr countryside east of the Euphrates River,” according to CENTCOM’s public statements. Read a bit more from Ku
BTW: Iran’s military chief is angry that Baghdad hasn’t handed over “separatist Kurdish dissidents stationed there and close their bases,” Reuters reports from Turkey today. The recent [violent] background there: “Major General Mohammad Baqeri was quoted three days after reports that Iran’s Revolutionary Guards fired seven missiles at the base of an Iranian Kurdish armed opposition group in northern Iraq, killing at least 11 people.”
Baqeri also took an indirect swipe at Saudi Arabia in the Tuesday row, which you can read about in more detail, here.

Attention Yemen watchers: West Point’s Combating Terrorism Center has a real treat for you this week — 5,300 words on “The Houthi War Machine: From Guerrilla War to State Capture.” It comes from Middle East analyst Michael Knights of the Washington Institute. He took three trips to Yemen’s frontlines this year alone, and has returned with a whopper of a report on the under-studied group.
Some of his findings: The Houthis are now a fairly highly-evolved guerilla fighting force that happens to have ballistic missiles. For example, on the former point, Knights writes that the Houthis “are extremely adept — and utterly ruthless — at blending with civilians, for instance by almost always entering [and] departing frontlines without weapons (and falling on on pre-positioned caches). If they're not struck, or if [civilians] are struck, it’s a win for them.”
However, the group is “much less adept at major offensive operations,” he writes. “In fact, they really suck at them and get chewed up badly by anyone who is alert [and] has airpower.”
What does this mean for the conflict moving forward? Read the full report, here. Or subscribe to the Defense One Radio podcast, where we’ll be speaking with Dr. Knights this week as he breaks down some of the highlights of his travels and analysis.

A word about Islamic insurgency trends in Africa: “In 2010, there were five recognized militant Islamist groups operating on the continent: al Qaeda (in Egypt and Libya), al Qaeda in the Islamic Maghreb (AQIM), al Shabaab, Hizbul Islam, and Boko Haram,” the Africa Center for Strategic Studies wrote almost a week ago off one of their summer reports.
The update: “By the end of last year, there were over 20.”
On the more recent bright side, “While fatalities linked to militant Islamist groups have increased 288% since 2010, they have dropped by almost half since 2015… almost entirely due to the decline in deaths associated with Boko Haram.” Dive into that report, here.

Happening Thursday at 11 a.m. EDT: Defense One’s Patrick Tucker and IARPA’s Kerry Long discuss the challenges of securing data in a connected world—from cloud security to unauthorized applications to malicious insider threats—and how the latest technology is helping the U.S. military plug its leaks.
The official theme: “Defending military data: Challenges and best practices in a connected world.”
You can watch that via a webcast (registration required) right here.