WASHINGTON -- In the old days, 10 years ago, jihadists vowed death to Western imperialism on audiotapes that couriers smuggled out of mountain hideouts and passed to satellite TV stations.

The next generation of militants has a much simpler way to proselytize: Twitter.

For years, Islamist extremists have struggled to outsmart the censors in online forums – with their videos yanked from YouTube, their pages flagged on Facebook and their message boards hacked – but Twitter still offers a rare unfiltered space for the groups, according to analysts who monitor militants’ online presence.

On one recent Sunday, for example, the Syrian jihadist group Jabhat al Nusra sent out a flurry of tweets from its official account, joining the Somali militants from al Shabab, Afghanistan’s extremist Taliban, and other hard-line Islamist fighters from Kenya and Yemen on the microblogging service that claims more than 140 million users.

Analysts said the groups are using the service mainly to add jihadist analysis to current events such as the conflict in Syria, or to reach out to young, disgruntled Muslims who might be on the fence about taking up arms to fight Western policies or authoritarian regimes.

“On Twitter, they get more reach to expand their propaganda. They can reach the ‘swing people,’ and try to attract more sympathizers,” said Murad Batal al Shishani, a London-based researcher of jihadists who’s closely monitored their Twitter feeds for months. He’s written on the subject for the BBC and other media. “They’re focusing on current events – Syria, or supporting a revolution here or there – but they are not using it for operational activity or to communicate among themselves.”

Twitter representatives didn’t respond to requests for comment. There appears to be no active campaign to curb extremist accounts, and the company so far has resisted critics who argue that such users be booted from the site.

Earlier this year, the U.S. government pondered disabling the account linked to the Shabab, Somalia’s al Qaida offshoot, but that account is still active, with militants last week gleefully tweeting about the death of their longtime enemy, Ethiopian Prime Minister Meles Zenawi. The media outlet of the al Qaida-linked Yemeni group Ansar al Shariah is still on Twitter; ditto for Shabab’s Kenyan affiliate, the Muslim Youth Center.

And when it became clear that the Taliban were on Twitter to stay, U.S. forces engaged in tit-for-tat tweeted barbs, a bloodless reflection of the war on the ground.

“The Taliban was in a Twitter fight with the ISAF’s Twitter account on a number of occasions,” said Aaron Zelin, who researches militants for the Washington Institute for Near East Policy and blogs about them at Jihadology.net. He’s working on a forthcoming report on the social media habits of jihadists. ISAF is the acronym for the U.S.-led International Security Assistance Force in Afghanistan.

Instead of being spooked by the public nature of Twitter, Islamist militant users continue to grow in number and stature on the service. Some jihadist fans also have opened unofficial accounts in the names of their favorite militants, such as Ayman al Zawahiri, the al Qaida chief whose whereabouts are unknown, or Anwar al Awlaki, a militant American cleric who was killed in a U.S. strike in Yemen.