The 'mother of all bombs', dropped by the United States in Afghanistan on Thursday is the most powerful non-nuclear bomb the world power has at its disposal - one has to return to World War Two to outdo the scale.

Marking its first deployment in combat, the MOAB became the most powerful single bomb used by the US since the atomic bomb that hit Nagasaki, which effectively drew the Second World War to a close.

The Massive Ordnance Air Blast (MOAB) is just over 9 metres in length and weighs in at almost 11 tons. Intended to detonate above ground, the bomb produces massive shockwaves which penetrate into the earth.

Leaving a great mushroom cloud in its wake upon detonation, the resultant force is designed to cripple underground tunnel systems.

Initially falling from an MC-130 cargo plane by parachute, on-board GPS systems guide the munition to its target before detonation, with the shockwaves produced able to be felt about 2 and a half kilometres away.

Thursday's bombing was intended to dismantle a cave and tunnel complex in the Achin district of the eastern province of Nangarhar, reportedly used by Islamic State militants to avoid detection from American spy planes.

Despite its power, experts suggest the strike is unlikely to turn the tides of a 16-year-long engagement of the United States, and as a result the use of the MOAB is likely to be symbolic, rather than tactical.

That angle reflects an intention in Washington to increase the pressure on Islamic State, with President Donald Trump labelling the weapon's use a "very, very successful mission."

John Pike, director of GlobalSecurity.org, a military policy research website, said the bomb is a "gee-whiz weapon," not a tactical one.

"You use a bomb like this to send a message," he said. "It demonstrates that the U.S., despite 15 years of bloody war, is here to stay."

With Washington Tribune