India, Feb. 9 -- Iran's Supreme Leader Ayatollah Ali Khamenei has, for the first time in nearly four decades, skipped a major annual meeting with air force commanders - a departure from a ritual he faithfully observed since assuming leadership in 1989.

The break in tradition comes amid heightened tensions with the United States and growing speculation about Tehran's strategic concerns.

The annual gathering, held each year on February 8, commemorates a historic episode in Iran's revolutionary history.

On that date in 1979, a group of air force officers pledged allegiance to Ayatollah Ruhollah Khomeini, a turning point that helped topple the Pahlavi dynasty and secure the future of the Islamic Republic.

Over the past four decades, the m...