A federal judge slapped a would-be terrorist, who plotted to blow up the Herald Square subway station, with 30 years behind bars yesterday - heeding calls from prosecutors who said the young radical was "perfectly willing to have people die." Shahawar Matin Siraj, 24, was convicted in May of conspiring to place an explosive device inside a garbage can or under a bench in the crowded West 34th Street subway station, which sits just beneath Macy's flagship department store. He wanted to bomb the station in retaliation for war abuses against Iraqis. "The defendant's role was central . . ....
