The discussion question suggests that there is a paradox between humanitarian assistance and an intervention.
Humanitarian assistance is voluntary external aid. An intervention is a forceful intercession in someone else's affairs.
If voluntary external aid is effective in alleviating a humanitarian crisis, this would suggest that (a) there is a functioning central government, (b) a somewhat stable political order, (c) an absence of armed conflict, (d) a functioning economy, and (e) adequate internal aid workers and distribution mechanisms.
If an intervention is necessary, this might suggest (a) the absence of an effective central government, (b) an unstable or non-existent political system, (c) the presence of armed conflict, (d) a failed economy, and (e) a lack of internal aid and distribution mechanisms.
In the latter case, a foreign country or multi-lateral coalition cannot effectively provide humanitarian aid, unless the underlying systemic problems are addressed. Any policy response needs to take into account the larger context in which the humanitarian crisis is occuring.
Some key questions to ask might include the following: Is the crisis a one-time event, such as a natural disaster (e.g., the tsunami in Indonesia, earthquakes in China); or is the humanitarian crisis an on-going disaster based on ethnic strife or a failed political and economic state (e.g. Somalia and Sudan)? Is foreign assistance welcomed by the local population and its government? Is there an armed conflict occuring, and are the groups that are fighting geographically intermixed (e.g. Iraq) or separated (e.g. Bosnia, Kosovo)? Is the aid being provided by a single country, a multi-national coalition, an international agency or a non-governmental organization, or a combination of the foregoing? What level of resources (personnel, money, goods in kind) is necessary to effectively address the humanitarian need, and are these resources available? What internal aid and distribution assets are available? What changes in security, culture, and the economic and political systems are necessary for the aid to be provided, and so the aid can make a lasting difference? Is there a willingness and ability to make the necessary changes?
If an intervention becomes necessary (i.e. a forceful external intercession in the affairs of a sovereign country), a humanitarian crisis cannot be solved through humanitarian aid alone. The intervening party must be willing and able to make or assist the sovereign country in making the necessary systemic changes that will make any humanitarian aid lasting and effective.