A man accused of a conspiracy to bomb the UK should not be convicted just because he had "wicked thoughts", an Old Bailey jury has been told.
Mr Amin (bottom left) broke down in the witness box
Omar Khyam, from Crawley in Sussex, had talked about terrorist acts but had not agreed to do anything, his lawyer said.
Joel Bennathan QC also said the main prosecution witness - a convicted terrorist - had lied in return for a reduced jail sentence.
Mr Khyam and six other men deny conspiring to cause explosions.
They were arrested after 600kg of fertiliser was found at a storage depot in Hanwell, west London, in March 2004.
In his closing speech, Mr Bennathan said: "If they talk about it for day after day, but are not agreed, that is not a conspiracy.
"You don't punish people for wicked thoughts."
He admitted his 25-year-old client had bought the fertiliser - but he had not "breathed a word" about it to his co-accused.
Mr Khyam was someone who was forever starting a scheme, then dropping it and moving on to something else, Mr Bennathan said.
He also criticised the prosecution's main witness, Mohammed Babar, who told the court he had plotted with the defendants to cause explosions in 2003 and 2004.
FBI's 'best friend'
Babar, who is in prison in the US awaiting sentencing after being convicted of terror offences, was interviewed by the FBI so much he was "trying lies on for size", according to Mr Khyam's barrister.
Mr Bennathan said Babar's motive throughout was to be the FBI's "best friend" and in exchange get his prison sentence reduced.
Babar flew from prison in the US to give evidence
Babar could expect to face 40 years in America, but in his testimony at the Old Bailey he said he hoped to serve less than four years.
Mr Bennathan said: "His interest is the bottom line. He is a Jihadi doing anything he can to get out of prison as soon as he can.
"Plead guilty and get out before you are 70. It's as simple as that."
The seven men deny conspiring to cause explosions likely to endanger life between 1 January 2003 and 31 March 2004.
They are Omar Khyam, 25, and his brother Shujah Mahmood, 19, both from Crawley, West Sussex; Waheed Mahmood, 34, and Jawad Akbar, 23, also of Crawley; Salahuddin Amin, 31, from Luton; Anthony Garcia, 24, of Barkingside, east London; and Nabeel Hussain, 21, of Horley, Surrey.
Mr Khyam, Mr Garcia and Mr Hussain deny a further charge under the Terrorism Act of possessing 1,300lb (600kg) of ammonium nitrate fertiliser for terrorism.
The Khyam brothers also deny possessing aluminium powder for terrorism.