Peter Hain has accused Home Secretary John Reid of "fanning" a row over plans for tougher anti-terrorism laws.
Peter Hain aid the row was "water off a duck's back"
It is the latest stage of a row between the cabinet ministers over a proposed new stop and search policy.
The Welsh Secretary said any tough new laws must be balanced with protection for civil liberties.
Dr Reid is reported to be unhappy with the criticism but Mr Hain told BBC Wales' Politics Show "macho posturing" does not make people feel safer.
Mr Hain's fear that extra powers could become a "recruiting sergeant for extremism" emerged in a leaked Cabinet letter last week.
Mr Hain said: "I don't believe in macho posturing on law and order and terrorism.
"The row that you have seen in the papers that John has fanned up, that's a matter for him. I don't mind. It's water off a duck's back, frankly."
It was important that people were not stopped and searched "arbitrarily on the street as Home Office briefings seemed to suggest a couple of weeks ago", the Welsh Secretary said.
"We've got to strike a very careful balance between being strong on security and protective of civil liberties."
The home secretary outlined tougher terrorism proposals in the Commons
Mr Hain declined to comment on the leaked papers, but added: "We've got to get away from big spin and macho posturing because that doesn't actually make people feel safer."
Asked if he had supported similar powers in the past, he said: "What you've seen in the papers is actually not true. That's all I'm going to say about it".
Mr Hain, who attended a Cardiff hustings on Saturday along with the other five contenders for the deputy Labour leadership, said he did not mind being considered an underdog in the race.
He added he was supported by six trade unions and was "well placed."
He said he had offered First Minister Rhodri Morgan advice on how to proceed in the Welsh assembly after last month's elections in which Labour secured only 26 of the 60 seats.
Mr Morgan is trying to fend off a threat from a "rainbow coalition" of Plaid Cymru, Liberal Democrat and Conservatives AMs.
Mr Hain said the poll was Labour's worst result for "80 years".
But he said: "I'm not pushing Rhodri to do anything. I'm working with him and supporting him as are my backbench MP colleagues in Westminster."