Ulsterisation refers to one part – "primacy of the police"[1] – of a three-part strategy (the other two being "normalisation" and "criminalisation") of the British government during the conflict known as the Troubles.
[2][5][6] Vietnamization was a policy to increase the proportion of South Vietnamese forces fighting in the conflict, while reducing that of the American military.
[7] Rees' aim was to put security policy on a more logical and rational basis, and along with the Chief Constable of the RUC, Englishman Kenneth Newman,[9] they produced the often controversial strategies of "criminalisation" and Ulsterisation.
[5][6][11] It was judged that the political impact in Britain of killings of British soldiers by the Provisional Irish Republican Army was greater than the deaths of local security forces members.
The drop in the number of non-UDR British Army casualties by 1976 helped prevent any build-up of sentiment in Britain for a withdrawal from Northern Ireland.