"Given that the group now calling itself the Sinai Province of ISIS really is a distinct group from ISIS itself in Syria and Iraq, motives for the attack are at least as likely to do with the Sinai group's objectives in Egypt as with what is going on in Syria," the analyst, who worked as an intelligence officer with the CIA and National Intelligence Council for nearly three decades, asserted.
The Sinai Province has been particularly active in the region since Egyptian army chief General Abdel Fattah al-Sisi removed the country's first Islamist president, Mohamed Morsi, from power. Ousting al-Sisi is, hence, one of the key goals ISIL's branch in Egypt is pursuing.
Pillar maintains that an attack on Egypt's key industry might seem as a logical and field-tested move for the militants.
"Attacking a plane carrying foreigners who vacationed at Sharm el-Sheikh is a way of attacking the tourist trade in Egypt, which is a way of degrading the Egyptian economy, which is a way of undermining the al-Sisi regime. This is basically the same strategy that an earlier generation of Egyptian terrorists tried to use against the Mubarak regime in the 1990s," the expert explained.
Pillar also mentioned that the plane crash could have been a retribution for Russia's unwavering commitment to root out terrorists in Syria. If so, other countries involved in counterterrorism efforts in Iraq and Syria should pay close attention to the incident.
"A search for US targets in response to what the United States is doing in Syria may already be under way," Pillar warned.