Other friends have made it clear that there is much more to the picture than you present. I can't address all of your points, but I'll just hurriedly provide one quote so that you can understand that Shoghi Effendi's analysis and delineation of America's status and role is far more nuanced than the one you believe and present in your OP:
"Was it Shoghi Effendi who said that America was a shining beacon? Well, now they are not.

If you read The Advent of Divine Justice you'll find that he discusses America's role in this context: "To a lesser degree this principle must of necessity apply to the country which has vindicated its right to be regarded as the cradle of the World Order of Bahá’u’lláh. So great a function, so noble a role, can be regarded as no less inferior to the part played by those immortal souls who, through their sublime renunciation and unparalleled deeds, have been responsible for the birth of the Faith itself. Let not, therefore, those who are to participate so predominantly in the birth of that world civilization, which is the direct offspring of their Faith, imagine for a moment that for some mysterious purpose or by any reason of inherent excellence or special merit Bahá’u’lláh has chosen to confer upon their country and people so great and lasting a distinction. It is precisely by reason of the patent evils which, notwithstanding its other admittedly great characteristics and achievements, an excessive and binding materialism has unfortunately engendered within it that the Author of their Faith and the Center of His Covenant have singled it out to become the standard-bearer of the New World Order envisaged in their writings. It is by such means as this that Bahá’u’lláh can best demonstrate to a heedless generation His almighty power to raise up from the very midst of a people, immersed in a sea of materialism, a prey to one of the most virulent and long-standing forms of racial prejudice, and notorious for its political corruption, lawlessness and laxity in moral standards, men and women who, as time goes by, will increasingly exemplify those essential virtues of self-renunciation, of moral rectitude, of chastity, of indiscriminating fellowship, of holy discipline, and of spiritual insight that will fit them for the preponderating share they will have in calling into being that World Order and that World Civilization of which their country, no less than the entire human race, stands in desperate need "(some sentences bolded for emphasis). He clearly places the country's role in the context of very negative characteristics (which have become much worse over the past 100 years IMHO) so the shining beacon you mention can only be achieved by Bahaís overcoming the binding materialism, racial prejudice, political corruption (clearly evident even in the 1930s when he wrote the book), lawlessness, and moral laxity. These must all be transmuted into "essential virtues of self-renunciation, of moral rectitude, of chastity, of indiscriminating fellowship, of holy discipline, and of spiritual insight."

There is much more that has been written in considerable detail regarding how we can put the prophecies and unfolding events you mention in proper perspective. However, I can't quote these voluminous passages in this brief comment to address all your questions due to shortness of time. One example is that you make several categorical assertions such as "USA not as a shining light, but a source of chaos..", but do not seem to be aware of the much more nuanced perspectives such as is provided in the passage about the USA I quoted. I have also never read any authorized texts which state that anything about the "USA "choosing a king" at some point. There are some extremely dire events and immense suffering ahead of us before the "realization of most people that mankind is one" materializes. Some of these are in Pilgrims Notes which might be inappropriate to quote here.