President Donald Trump's decision to move the US embassy to Israel from Tel Aviv to Jerusalem "was clear and explicit, and he revealed the true face of the modern Crusade," al-Qaida leader Ayman al-Zawahiri said in a recording circulated on social media this week. "Standing down and appeasement does not work with them, but only resistance through the call and jihad."

But, despite al-Zawahiri's new appeal, "reactions thus far don't show any sort of organized online campaign from either side," Rita Katz, director of SITE Intelligence Group, said in a tweet, referring to the social media channels of al-Qaida and the "Islamic State" (often abbreviated as IS or ISIS).

Reinventing itself

That silence may be indicative of a shift, according to Ian Oxnevad, a Middle East scholar at the University of California, Riverside. He told DW that while there wasn't much of a backlash, "that does not mean that it is not present."

"Even if the new anti-American animosity is mild throughout the Muslim world, those who are radicalized may be more inclined to seek out al-Qaida than IS ... given that IS may have alienated a number of people from the overall Islamist movement."

For Oxnevad, al-Zawahiri's new call for jihad is "primarily al-Qaida reorienting itself" after its main competitor, IS, suffered military defeat in Iraq and Syria, countries where it once controlled large swaths of territory.

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"This is a chance for al-Qaida to reinvent itself," Oxnevad said. "Al-Qaida can co-opt old IS networks and strategies while setting up new cells in Europe," which provides a "base of potential recruits along with a social infrastructure removed from new realities in the Middle East."

Al-Qaida in the Arabian Peninsula (AQAP) claimed responsibility for the January 2015 attack on Charlie Hebdo's offices in Paris, which left 12 people dead

'Back on the map'

Since the rise of IS in 2014, al-Qaida has fought to become relevant once again by recasting itself as the leader of jihadi causes. The group often uses its opposition to US military and political policy in the Middle East as a means of garnering support, and taking up the plight of the Palestinians and declaring a new jihad is just one part of that strategy.

"The rhetoric is about branding and rebranding," Hassan Hassan, resident fellow at the Washington-based Tahrir Institute for Middle East Policy and co-author of ISIS: The Army of Terror, told DW.

"Al-Qaida also wants to capitalize on the weakening of ISIS to put itself back on the map as the preeminent leader of global jihad," Hassan said. "After all, these organizations are populist movements that jump to popular sentiments to gain support."

But it's unclear whether that strategy will translate to numbers on the ground. For example, in Syria, "al-Qaida's main branch has shrunk from a group that operated throughout the country to one concentrated in pockets in the northwest," Hassan said, referring to Hayat Tahrir al-Sham (HTS).

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At one point, HTS — which includes the group formerly known as the al-Nusra Front — had up to 30,000 combatants, according to the Washington Institute think tank. But Hassan said that figure is "grossly exaggerated," and is more "in the neighborhood of 10,000."

The death of Osama bin Laden dealt a major blow to the organization — Al-Zawahiri (right) took over in the aftermath

From survival to expansion

Since the attacks of September 11, 2001, a global coalition has targeted al-Qaida's leadership, assets and infrastructure. The campaign has notably dealt a major blow to the group's operational structures over the past decade, including assassinating former al-Qaida leader Osama bin Laden in 2011.

However, since 2014, the group has become less of a priority in the "War on Terror," most notably after the US streamlined its efforts against IS under former President Barack Obama.

Read more: Years after bin-Laden's death, al-Qaida weakened – but not finished

As such, al-Qaida has made inroads over the past couple years by further expanding on its model of a decentralized jihadist movement, most notably in Africa and Asia, Tomas Olivier, counterterrorism and intelligence manager at the Netherlands-based Twickelerveld Intelligence and Investigations, told DW.

"Its fluid organization structure facilitated its survival, and provided the organization with new, sometimes opportunistic, opportunities in mainly failed states like Afghanistan, Yemen and Somalia, but also in Algeria and Pakistan," Olivier said.

Al-Qaida's branches in North Africa, the Indian subcontinent and Arabian Peninsula "are gradually expanding their operations in which they try to discredit local governments, deliberately target foreign peacekeeping troops and exchange their traditional regional aspirations and intent for a more global scoop."