The immediate future must, ...

The immediate future must, as a result of this steady, this gradual, and inevitable absorption in the manifold perplexities and problems afflicting humanity, be dark and oppressive for that nation. The world-shaking ordeal which Bahá’u’lláh, as quoted in the foregoing pages, has so graphically prophesied, may find it swept, to an unprecedented degree, into its vortex. Out of it it will probably emerge, unlike its reactions to the last world conflict, consciously determined to seize its opportunity, to bring the full weight of its influence to bear upon the gigantic problems that such an ordeal must leave in its wake, and to exorcise forever, in conjunction with its sister nations of both the East and the West, the greatest curse which, from time immemorial, has afflicted and degraded the human race.
Then, and only then, will the American nation, molded and purified in the crucible of a common war, inured to its rigors, and disciplined by its lessons, be in a position to raise  its voice in the councils of the nations, itself lay the cornerstone of a universal and enduring peace, proclaim the solidarity, the unity, and maturity of mankind, and assist in the establishment of the promised reign of righteousness on earth. Then, and only then, will the American nation, while the community of the American believers within its heart is consummating its divinely appointed mission, be able to fulfill the unspeakably glorious destiny ordained for it by the Almighty, and immortally enshrined in the writings of ‘Abdu’l-Bahá. Then, and only then, will the American nation accomplish “that which will adorn the pages of history,” “become the envy of the world and be blest in both the East and the West.”

Shoghi Effendi: The Advent of Divine Justice