"just rest assured -- Jester is a freind of US," he writes.
He says he has taken down more than 179 jihadist websites with U.S. servers.
"US still have no idea where they come from," he writes. "they know it is J," he writes, referring to himself. "but not who J is."
th3j35t3r said he only takes down sites for 30-60 minutes.
"I could pull them down forever but i choose to do sporadic bursts," he says, so that authorities will either be alerted to the hacked website, and so they can continue monitoring its visitors if they had been doing so already.
He says he has a strategy to his hacking.
"I hit some sites a lot and other sites not so much," he says. "this is a tactic by hitting one site less it herds the target of these sites into it where they are easilt monitored, its easier to monitor a smaller space."
What keeps th3j35t3r from abusing his hacking abilities to harm U.S. interests?
"my dead friends kep me from dong that, and also my alive ones. ;-)," he writes back. "and my drive and reason for embarking on this in the first place."
He has plenty of fans online, illustrated by the replies and retweets he gets on Twitter.
One person tweets: "Thanks Jester for doing Obama's job", and another: "There should be more people like you around!"
Yet he has detractors, too.
"#wikileaks is the only thing keeping us from living under a fascist regime. the only ppl they've harmed are corrupt politicians," one person tweeted.
th3j35t3r says he wishes to remain anonymous, and turns down TV interviews. Nevertheless, he has become an underground celebrity among techies, and has been interviewed by tech blogs.
"I am not about the limelight," he writes, "I am about the issue."
He will not confirm his nationality, location, age or occupation, but will talk about how he got into hacking.
He says he is under 50-years-old and over 30, and began coding when he was 10 years old. He says he was "thirsty for knowledge about how computers worked, and fascinated by the fact that just a guy and a keyboard might make a difference to something."
However, he says he was "always drawn to applying myself withiin the military," and thus, did his time as an airborne frontline combat trooper, twice.
th3j35t3r says he isn't targeting Muslims -- just those who try to recruit terrorists online.
In the past two years over 60 Americans have been arrested or convicted on terrorism charges, including some who made contact with jihadist recruiters online.
"I have no problem with muslims, I have many muslim friends who would if they knew support me. It's the online grooming, recruiting, training and tasking I have issue with," he writes. "I wouldnt say I am a protector of muslim youth particularly, thats hopefully a by-product."
"islam isn't the issue," he says. "radical islam is."