Explain the line “A terrible beauty is born” from Yeats’ poem “Easter 1916”

Wherever green is worn,
Are changed, changed utterly:
A terrible beauty is born.

This is the concluding part of W.B.Yeats’s patriotic poem Easter 1916. After paying his eulogy to the great Irish patriots who stood, fought, and died to liberate their land from the British occupation, the poet here asserts that everything is brought to an utter change by that great sacrifice of Easter 1916.

The Easter Rising of 1916 by the Irish patriots resulted in a disastrous result. The leaders of the Rising and many more were slain by the brutal force of the British imperialistic power. Yet, out of this dreadful, ghastly matter has come a grand and glorious history – the history of the patriotic struggle of suffering and sacrifice. The cause of Irish freedom in the emblem of green is proudly worn by the Irish patriots. The Easter Rising has brought about a thorough, drastic change in the situation. From the state of humility and obscurity has come the grandeur of heroic sacrifice and the splendour of the love for the land. That dreadful blow ever the British power has brought out an unblemished glory to dazzle.

The expression is an unequivocal eulogy by the poet of the Irish freedom movements and bears out his patriotic fervour and devotion to the cause of his own land-Ireland.

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