Do you think it is ever right for one country to become involved in the internal affairs of another?

From my point of view, countries really should not stick their noses into another country’s problems unless their help is seriously needed. But in recent times, countries intervened when they shouldn’t and when they should, they didn’t. This prompted me to infer that government intervention comes with a hidden agenda, sometimes not so hidden. In the case of Iraq, America invaded with intention of liberating ill-suffering Iraqis from the demonic but now-dead Saddam Hussein. Instead, it is reported that at least 650,000 innocent Iraqis ended up dead due to the invasion. So, was the invasion a sound decision by the Americans after all? Will the Iraqis be better off without the intrusion of the US? I think they will be.
Where were all the help when it matters most? Cyclone Nargis tore through Myanmar, taking along with it hundred of thousands of lives and stranding others to fight for their own survival. Why didn't countries pour into Myanmar with their aid? Some may argue that Myanmar's Juntas were resistive and cynical towards foreign help but why were other nations so concerned over the Junta's stand? Why didn't they just enter the countries with their aid? I'm sure countries can 'barge' into Myanmar on the account of human rights to aid those in need. After all, it is evident that other countries's aid can be very beneficial to the survival and reconstruction of a place devestated by natural disasters. Banda Aceh is one such example!
Thus, i am in favour of government intervention if help really can be rendered to those in need but i feel country should also be given the rights to solve their internal problems, but if they fall to do so, then they should allow others to do it for them. Unlike the old and stubborn Junta....