You can’t act irresponsibly and then say ‘it’s Ok – have bitachon’. If releasing 1000 terrorists creates a dangerous threat to Jewish lives then maybe it shouldn’t have been done.
There are halachos about Pidyon Shivuyim – it’s not a free for all, to-be-judged-by-emotion issue. I am very happy for Gilad Shalit and his family but in reality the complex question of Pidyon Shivuyim here should have been decided al pi halacha.
The Maharam MiRotenburg forbade his Kehila from paying a huge ransom when he was imprisoned for fear it would encourage further false imprisonment. He died in prison. He didn’t say ‘ Oh well – it will be Ok let’s have bitachon’ – he acted responsibly in accordance with the halachah. If I am not mistaken, his stance paid off and no Rov or Community leader was imprisoned again for a very long time.