He is widely published on military and national security affairs, including in his book Expendable Warriors (2007) and in a regular column for the Examiner.

[2] Excelling both as a student and as an athlete, Clarke was accepted to both Stanford and Harvard but, to the surprise of many of his Ivy League-bound classmates, elected to attend the U.S. Military Academy at West Point.

The initial enemy assault was beaten off by the courageous efforts of the RF Company and by almost constant barrages of artillery using variable time fused rounds.

After the initial assault was broken, the enemy simply backed off and using the positions he had already prepared, attempted to destroy the key bunkers by recoilless rifle and rocket propelled grenade fire.

At this time the police station was still communicating with the District Headquarters and made it possible to put effective fire on the enemy moving into the village.

For the next four hours there were constant attacks or probes against the compound which were beaten off by the valiant efforts of Bru (Montagnard) PFs and the Vietnamese RFs working as a coordinated team and reinforced by the CAP Marines, which SGT Balanco moved to meet the threat.

A B-52 strike was requested and it was later learned that the strike had hit the Regiment, The next morning the evacuation of District Headquarters was ordered after Colonel David E. Lownds, the commander of the 26th Marine Regiment, ordered the evacuation of the Marines from the garrison and denied further artillery support—over 1200 rounds had been fired in the last 24 hours in support of the District Headquarters defense.

The District government, forces, and advisors spent the next two and a half months in exile at the KSCB where they dodged artillery rounds, took part in the defense of the Combat Base, and operated an intelligence net.

During that time the "agony of Khe Sanh” played on the front pages and news reports on Main Street thought out the country.

Because of a shortage of officers, Clarke was forced to leave UCLA before finishing his PhD for a teaching post in the Department of Social Sciences at West Point.

Clarke's training of the Dagger Brigade for desert combat would prove fortuitous as days after giving up command in 1990 to Colonel Tony Moreno, Iraqi forces overran Kuwait.

The 2nd Brigade eventually helped lead the ground invasion during Operation Desert Storm capturing Safwan, the site of the cease fire talks between General Norman Schwarzkopf and Iraqi commanders.

While at the Army War College he published extensively on military modernization and helped shape the work on conflict termination studies.

In late-1992 this work was put to the test when, following President George H. W. Bush's deployment of forces to Somalia for Operation Restore Hope, Clarke led a team to consult with the Joint Chiefs of Staff on building an exit strategy.

Army Chief of Staff General Gordon R. Sullivan presided over the ceremony and awarded Clarke the Legion of Merit.

His work on defense issues, national security strategy and knowledge of the Middle East has led to his advising at least two members of the U.S. Senate.

Clarke is the author of Expendable Warriors (Praeger Security International, 2007) with a foreword by former Joint Chiefs Chairman General John Vessey.