And in Bashier's case, they were right. They just needed the right bait. Originally they were going after his head appealing to his sense of duty. They finally succeeded once they lowered the target by about three feet.
My take on the action was that Bashir was aware what exactly he was being asked to do here. His mission was to destroy the Breen's slipstream drive plans and (heavily implied) punish them for their act of wetworks. In the 1995 Michael Douglas movie, "The American President" an American plane is destroyed by Libyan agents and rather than go to war, he has their intelligence headquarters bombed instead.
Julian's mission is to destroy the slipstream drive and do so in a manner which is hard rather than soft. Destroying the shipyards is something they didn't need to do. They could have just plotted to blow up the ship itself or sabotage it. This was a revenge attack designed to punish the Typhon Pact so they didn't think they could causally murder Federation citizens again. Julian could have thought of a way to make it so he and Sarina were never even noticed but Sarina made it clear the governmen expected (and wanted) it to be at least SLIGHTLY messy.
It's nasty-nasty business and against the kind of stands which Picard used to take up for. However, ST is at its best when it's examining those stands. The Federation turned over the Phase-Cloak device. It also hunted the Marquis mercilessly, showing their commitment to their treaties.
The reaction this did? Neither the Romulans or Cardassians were inspired to show any similar level of devotion to peace. In a way which is against my Christian beliefs, the Feddies turned the other cheek and they were slapped there too. It's a dark road the Federation is walking but figuring out how to navigate out is a good lesson.
See i found this totally out of character for Bashir - I do not believe that he would ever kill anyone except in all our conflict/self-defence, and even then i find it unlikely. I simply do not believe that he would ever walk into an office and kill 6 people as he does in this novel. I'm sorry David Mack - i have loved some of your novels, the destiny trilogy in particular, but this is not Bashir. Kira - yes, Garak, off course, but there is no way that Bashir would ever behave in such a cold-blooded fashion - and dont throw sloan and section 9 at me.
This is where differences of interpretation come in. In my mind, Bashir has always had a dark side that the show hinted at but never really fully explored. Basically, Bashir is not as fulfilled being a Doctor as say, McCoy or Crusher. It's his calling but it's not his VOCATION. He's not really content to be a Doctor and isn't all that happy with it. He values life but not so much he's incapable of being a soldier.
His status as an Augment results in a lot of retcons but, basically, Julian has regrets about not being a tennis pro and it's implied he went to Bajor specifically because "Frontier Medicine" gets the LAW off his back.
In a very real way, Julian's friendship with Garak symbolizes that he wants more and perhaps sensed they both were kindred spirits (people underperforming at their abilities). I think David Mack nicely captures that he feels like he's wasted as Deep Space Nine's Doctor. He knows he could be Louis Pasteur and he's stuck being a local pharmacist. He could be many other things than "just" a Doctor and this eats at him. In a way, being an Augment means he could be good at ANYTHING so he's never really content.
Ezri Dax said that Bashir played at being a spy and this illustrates she doesn't really KNOW Julian the way he knows her. Julian is every bit as capable as Dax w/ her hundreds of years of memories. Julian could be a Captain of a Starship like the Aventine. Really, Julian won the Frigging Dominion War because of his actions during it. Does he get the Federation Medal of Honor? No. A parade? No. Do Augments as a whole get treated any better than X-men mutants? Not a chance.
Julian wants to be GREAT at something. Being a spy tantalizes him with this prospect because Section 31 (grotesque as it was) didn't shy away from him. He was never tempted to join but being a spy for them gave him a taste for being a larger than life hero, IMHO. If Starfleet ever just offered Julian his own version of the Normandy from Mass Effect and a license to raise hell, he'd be off DS9 and out of medicine in a heartbeat.
He'd feel guilty but he'd do it. He's Doc Savage and wants MORE.