Why should developed countries try to help poorer countries? Because the status quo of most poorer countries is absolutely impossible to decouple from the exploitation, consumerism, and resource redirection carried out by wealthier countries.
Even in the U.S. the rich and those in power and those in business depend on the poorer masses to do the dirty work. And in agriculture and even construction, the U.S. depends on illegal immigrants and barely legal immigrants to do a lot of the work.
The U.S. is still trying to work out the problems of having kept some people disenfranchised. And the U.S. became the U.S. by taking the land and sticking the Native people on reservations.
There are people working for and against bringing about change in all these things. What are the Baha'is going to do? Besides say, "Well, all people should get along and treat each other as members of one human family." Those with wealth and power aren't going to give in easily. But are those people that depend on the rich for jobs going to rock the boat and cause trouble? They've got mouths to feed and gas to buy and utility bills to pay.
The Baha'i Faith needs, and is waiting for, the total collapse of what they call the "old world order" and then they will put God's "new" order into place. A new civilization with no more wars, no hunger or poverty and all the rest of the good stuff.
"… Both within and without the Cause of God, powerful forces are operating to bring to a climax the twin tendencies of this portentous century. Among the many evidences which reveal this process may be cited, on the one hand, the continual increase of lawlessness, terrorism, economic confusion, immorality and the growing danger from the proliferation of weapons of destruction, and on the other, the world-wide, divinely propelled expansion, consolidation and rapid emergence into the limelight of world affairs of the Cause itself, a process crowned by the wonderful efflorescence of Mount Carmel, the mountain of God, whose Divine springtime is now so magnificently burgeoning."
The House of Justice noted your comments that you have read what Bahá’u’lláh had to say about the collapse of the old world order and the coming of the new, and that in recent times friends returning from their pilgrimages spoke of meetings with Hands of the Cause and members of the House of Justice in which the coming of great world upheavals was related to a time 'around the end of the Five Year Plan and afterwards'. The House of Justice points out that calamities have been and are occurring and will continue to happen until mankind has been chastened sufficiently to accept the Manifestation for this day. ‘Abdu’l-Bahá anticipated that the Lesser Peace could be established before the end of the twentieth century. However, Bahá’ís should not be diverted from the work of the Cause by the fear of catastrophes but should try to understand why they occur..."
(From a letter written on behalf of the Universal House of Justice to an individual believer, April 15, 1976)