But, at 7:30 AM on a hot summer morning as we drove towards the Mexican security checkpoint on the bridge, Mary was calm.

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That may help to explain why Mary Robinson's election in 1990 heralded a more liberal and less Catholic country while seven years later Mary McAleese's "bridge-building" theme foreshadowed what politicians south of the border believe was the reconciliation of the Good Friday Agreement a year later.

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Then there is the bridge at Chappaquiddick, where Mary-Jo Kopechne drowned when Ted Kennedy's car (along with his White House hopes) sank in 1969.

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But others have noted that his legacy of public service was counter-balanced by heavy drinking in his early years - and the death of a female companion, Mary Jo Kopechne, in 1969 when he drove off a bridge at Chappaquiddick in Massachusetts and fled the scene.

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Early on July 18, 1969, Kennedy drove his car off a bridge on Chappaquiddick Island in Massachusetts and his passenger, Mary Jo Kopechne, drowned.

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