Al Qaeda propaganda has gone into overdrive to try to discredit US President Barack Obama's charm offensive among Muslims, but its outpouring of rage will ring hollow if it cannot land a punishing new blow in the West.
Four years after the last al Qaeda-linked bombing in a Western country, Mr Osama bin Laden's shadowy network is pumping out videos of increasing sophistication and frequency to stir hatred of Mr Obama, the West and its ally Israel.
Radical clerics tend to echo the anti-Obama theme.
"Be careful of this devious devil, he is more dangerous than the rash devil," Saudi preacher Sheikh Abdulaziz al-Julayyil wrote in May, referring to Mr Obama's predecessor George W. Bush.
There is a multinational hardcore audience for al Qaeda's mostly-online material: It praises suicide bombers, urges fighters to launch attacks, prods wavers to join up or give financial backing and teaches that Mr Obama is just as bad as Mr Bush.
But experts who track the output say the lack of an al Qaeda-linked strike in the West is hurting its credibility and limiting the group's appeal to the already-committed.
"Propaganda of the word is enormously important for them, but they would prefer a bit more propaganda of the deed," said Richard Barrett, chief of the UN al Qaeda Monitoring Team.
Al Qaeda propaganda "is no longer as powerful as it was because its audience has shrunk and it has not come up with anything new. Nor has it managed to carry out major attacks".
The last al Qaeda-linked strike in a Western country was the 2005 London bombings that killed 52.
Tougher security in the West and killings of middle-rank Qaeda experts are among the main factors that have weakened the group's militarily.
London-based Saudi dissident Saad al-Faqih said that if al Qaeda struck in the West again, it could regain popularity among Muslim communities and make its followers "jubilant".
If and when such an attack happened, mainstream Western media would refocus attention on al Qaeda and no longer see its statements as "mere words" as they did at present, he said.
"The balance between al Qaeda and the US in the hearts and minds of the Muslim public is not linked to statements and speeches as much as it is linked to actions," he added.
Preacher Muhammed Tahir ul-Qadri, last Sunday conveyed a message of moderation, peace, inclusion and understanding at Al Hidayah, a youth camp at Warwick University in Coventry, central England.
But militant media output has an inverse link to attacks, says Dubai-based analyst Mustafa Alani, as recruitment and funding suffer without the inspiration of successful bombings.
The year 2007 was the busiest so far for al Qaeda's media arm, as-Sahab: Defeats for al Qaeda in Iraq and Saudi Arabia prompted an outpouring of statements and videos to persuade militants and potential followers that it was still relevant.
After a post-2007 dip, the publication rate by core leaders is rising again. Their frequency this year is set to surpass 2006 and last year, and become the second-busiest year ever, says Intelcentre, a US-based terrorism monitoring company.
This time, it is not only a pause in military activity that is triggering the torrent of words, it is Mr Bush's replacement by Mr Obama, who is proud of his Kenyan father's Muslim heritage and therefore cannot easily be stereotyped as a Muslim-hater.
Worryingly for al Qaeda, Muslim communities around the world appear to have responded favourably so far to Mr Obama the person, even if they continue to dislike and distrust US policy.
Al Qaeda is still adjusting to the departure of Mr Bush. In his 2004 "Message to the American People", Mr bin Laden said Mr Bush had done everything possible to start wars and provoke Muslims, so much so that the White House "seems to be playing on our team".
Mr Bin Laden and second-in-command Ayman al-Zawahri pounced on Mr Obama's offer in a Cairo speech in June of a "new beginning" with Muslims based on mutual interest and respect, denouncing him as a deceptive criminal.
Aware that the propaganda battle centres on the persuadable, rather than the already-committed, al Qaeda has pounded away at Mr Obama in subsequent weeks but has yet to land a telling blow.
Thomas Hegghammer, a political scientist at Harvard University who studies violent Islamism, said al Qaeda was doing everything it could to portray Mr Obama as the figurehead of a system that represses Muslims regardless of who is president.
But the group remained clearly worried by his potential effect on Muslim opinion, he said.
Al Qaeda's task is complicated because it is still trying to recover from an backlash created by suicide attacks on civilians in Iraq in 2004-06 that alienated many Muslims, experts say.
In a recent lengthy interview with as-Sahab, Mr Zawahri mentioned Mr Obama no less than 26 times, according to Jarret Brachman, a specialist on al-Qaeda strategy and propaganda.
"Whatever he is ranting about is what he's most concerned about," he said.
"He's caught in a Catch-22. On the one hand, he has to keep talking to keep the jihadist movement on track, but the more he talks, the more he shows his cards, particularly about where he thinks the jihadist movement is most vulnerable."