I guess at the moment, the powers that be are worried that if they send troops into Zimbabwe they'll get slammed for overstretching our troops and for starting another 'unnecessary war'. Also, the problem is that too many other countries would get involved... Many African countries would side with Zimbabwe, but probably (and most worryingly if the UK was thinking about going into another war without a mandate from the UN) so would China, since Zimbabwe spends half of its GDP a year on arms from there. So if Britain were thinking of going it alone, they'd have to think carefully. However, why the UN hasn't got involved with anything 'more persuasive' than diplomacy so far is absolutely beyond me... it's disgusting IMO.