An Irishman too nasty to bring peace and concord? (13)

I believe the answer is:

harmonisation

'peace and concord?' is the definition.

'an irishman too nasty' is the wordplay.
'nasty' indicates an anagram.
'an'+'irishman'+'too'='anirishmantoo'
'anirishmantoo' with letters rearranged gives 'HARMONISATION'.

'to bring' is the link.

I've seen this clue in The Telegraph.

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