Joe Biden has recalled the Queen's message to the US following the 9/11 attack in 2001, and it remains particularly poignant 21 years later.
"Her ambassador read a prayer at a service at St Thomas Church in New York, where she poignantly reminded us that 'grief is the price we pay for love'", he said during yesterday's commemorative speech.
"Many of us have experienced that grief, and you’ve all experienced it."
A moment of silence was held for those lost in the New York terrorist attack.
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