Syrian commanders say their troops along the border with Iraq are making strides in nabbing militants intent on staging suicide attacks in Baghdad. Syrian soldiers in a pickup truck patrol the area of their country's border with Iraq. But, the commanders say, they could do a better job if they were able to obtain modern equipment denied to them because of sanctions and if they received cooperation from the U.S. military. The commanders also say U.S. aircraft occasionally violate Syria's airspace, a situation that points to the lack of coordination between the countries. "We work within our abilities," said Gen. Khaklil Al-Khaled, a provincial military commander in northeastern Syria. "The border constitutes a daily obsession to us, to prevent infiltration and confront the contraband groups and jihadist groups that infiltrate the border."  Watch what life is like on the Syrian border ». Syrian commanders were interviewed by CNN along the border, where Syria and the United States have a complicated relationship. The Syrian government "began limited cooperation with the United States in the global war against terrorism" after the September 11, 2001, attacks, the U.S. State Department has said. The United States has long criticized Syria for being a staging ground for insurgents who infiltrate Iraq in the Euphrates River valley of Anbar province and conduct attacks in the towns along that waterway and in Baghdad. It has also criticized Syria for its ties to Iran, the Lebanese militant group Hezbollah, and the Palestinian movement Hamas. Syria says it is doing what it can to thwart insurgent activity and the United States in turn has softened its negative rhetoric toward President Bashar Al-Assad's regime. They say they've arrested many foreign fighters and have confiscated many weapons. The number of monthly insurgent strikes in Iraq has dropped dramatically recently as Iraqis who once backed insurgents in Anbar province have turned against them. Still, some insurgent activity continues in Anbar and along the Nineveh province section of the Iraqi-Syrian border. Al-Khaled said Syrian troop outposts are strung along the vast, sandy 385-mile Syria-Iraq border, with 12 soldiers per post. The troops have erected a sand wall and embark on daily foot and vehicle patrols. "There have been many arrests of jihadi groups that infiltrate the Iraqi side, and they have been turned to the authorities. These jihadi groups belong to different nationalities, such as Egyptians, Saudis, Moroccans, Tunisians, and Libyans that fight in Iraq," Al-Khaled said. The Syrians chafe at criticism from Americans for not doing a better job. The Syrians say they are using antiquated equipment because sanctions by the United States prevent them from upgrading. They say they lack night surveillance equipment, automatic weapons and other items they believe would help them. Al-Khaled said Syria doesn't like the U.S. administration casting blame on Syria for lax border security when "America itself cannot control its border with Mexico." The Syrian military said it has no communication with U.S. commanders along the border -- something that troubles Syrian commanders. Al-Khaled said communication would help deal with problems such as U.S. planes entering Syrian airspace. "Every now and then there are airspace violations -- sometimes not less than five to six times per month with their military jets and helicopters," Al-Khaled said. He said Syria lodges its complaints with an Iraqi liaison officer. Americans say the errors are tactical or human, he said, but he doubts those assertions because of the U.S. military's acumen and resources. "This is an issue that concerns both sides," he said. "There should not be any lenience from their part in violating the border of a free, sovereign state." Mohammed Askari, spokesman for Iraq's Defense Ministry, declined to comment, saying these are Multi-National Forces issues. The U.S. military has not responded to a request for comment.

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Syrian military says it has arrested many militants trying to get into Iraq. Syrian commanders say they could do better without U.S. sanctions. Sanctions prevent military from having modern equipment, Syria says.

The scrolling list of online student activities for Tuesday, April 20, lists a spring play rehearsal, a talk by "famous photographer, John Fielder" -- and "NO SCHOOL." It's a tough day to be within those walls. It was there, 11 years ago, that Eric Harris and Dylan Klebold embarked on a massacre -- shooting 12 classmates and a teacher dead and injuring 23 others before turning the gun on themselves. Columbine High School was forever etched into the psyche of America. The top news story of 1999. An iconic shooting. An event prompted intense debate over gun control. "A day that changed us forever," as former President Bill Clinton said at 10th anniversary observances last year. Clinton, who was in the White House at the time of the killings, said he was personally inspired by the courage of the Columbine community. Tuesday marks anniversary number 11, an odd-year milestone that millions of Americans will let come and go without notice. But for the survivors, for the victims' families and friends, time's steady march is not enough to dull the pain. The memories are still raw in Littleton, Colorado. Principal Frank DeAngelis attended a teary prom last weekend when Columbine crowned a king and queen with special needs. An act of goodwill and fraternity. An act exemplifying the human spirit. "This," DeAngelis told CNN affiliate KMGH in Denver, is what Columbine is all about." In far away Dallas, Texas, Jordan Niland, 17, said he is sure to pick up his telephone Tuesday. He will dial the number of Richard Castaldo. Castaldo, a junior at Columbine in 1999, suffered five gunshot wounds to his chest, back, arm and colon that left him paralyzed from the waist down. Niland was a young boy then. But after seeing Michael Moore's documentary, "Bowling for Columbine," he struck up a MySpace conversation with Castaldo. The two have been friends since." "The anniversary means so much to me," Niland said. "I have had the privilege to talk and get to know a survivor and to fully understand what really went on that day." If people could personally hear Castaldo's story, Niland said, they would stop to reflect on this day. Because such a horror, he said, should not be forgotten. And because life goes on. A Columbine memorial dedicated in 2007, is sure to be visited Tuesday. But like the tragedy itself, the memorial, meant as a place of reflection, is incomplete, gaps running through it like the voids in people's lives. The memorial park has posted a wish list to complete the peace it is intended to bestow. Hackberry trees, lavender mist, spirea, purple asters. And 24 columbines. Any variety will do, the memorial's website says. As long as they are columbines.

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Columbine High School will be closed on day of anniversary. "Day that changed us forever," former President Bill Clinton said last year. Memorial park has posted a wish list of items sought to complete it.