Well I have made the distinction between two situations, Rwanda clearly falls into one:
a) Open conflict, or verging on. (eg. UN involvement to halt genocide)
b) Minor cultural matters. (eg. healthy & saftey brings an end to, or significantly alters, a harmless tradition)
In favour of intervention in the first, oppose it in the second. The West should have re-involved itself in Rwanda.
Actually, having read back on the Divide and Rule article, it strikes me that there is a mid-point, in which b) can lead to a).