Ansar Beit al-Maqdis, is responsible for the downing of the Russian A321 passenger jet over the Sinai Peninsula on October 31 that killed all 224 people on board, US Central Intelligence Agency (CIA) Director John Brennan told the Senate Intelligence Committee earlier on Thursday.
Macgregor, a military historian and leading US tactician, pointed out that the terror group had established itself in Sinai after Muslim Brotherhood leader Mohammed Morsi was elected president of Egypt.
"Ansar Beit al-Maqdis emerged from the chaos in Egypt under Morsi. It has now declared itself the ISIS [Daesh] branch in the Sinai," Macgregor noted.
The terror group was seeking to repeat previous Islamic State gains in other countries and was escalating its assaults on long-established international peacekeeping forces between Israel and Egypt in the Sinai, Macgregor observed.
"They have already attacked the Sinai task force that guards the border between Egypt and Israel," he recalled.
So far, the Egyptian army had proved unable to destroy the group or roll it back, Macgregor said.
"The problem is the inability of Egyptian ground forces to systematically annihilate the group in the Sinai," he stated.
The US military continued to support Egypt, but was not engaging Ansar Beit al-Maqdis directly, Macgregor added.
"We can and are doing much to help them, but we cannot intervene on Egypt's sovereign territory with our ground forces to eliminate this home grown Sunni Islamist organization," he concluded.
Doug Macgregor holds a doctoral degree in international relations from the US Military Academy at West Point. He commanded in the Battle of 73 Easting, a decisive tank fight during the 1991 Gulf War.