Watching the reactions of people in such a large audience, some mouthing the words - presumably Ukrainians - many agog, others in tears, especially at the end, and I shed a few myself.
She gave a beautiful performance, from her solo entry onward, subtle, not bombastically operatic, and Rieu did a superb job with the arrangement, which rose joyously toward the end, but never swamped Reker's delicacy of touch and obvious love of the piece and all it stands for. Considering the vast orchestra, choir and brass band, his was no mean achievement. Then she opened her hands at the end, when all the choristers, band and orchestra dropped out again, as if she was releasing a swallow, and for a moment you could have heard a pin drop until the audience erupted.
And then, of course, there's the political and human background, and the history of the composer and the story behind him and the piece, which I'm really pleased Goonch fleshed out in the reply above.
What a remarkable people. The world's a better place for their being in it. And what a life-affirming performance. Thanks for sharing your background. Slava Ukraine.