And Dr. Oppenheimer, among other ecologists, points to global warming as perhaps the most significant long-term factor.
Most foreign-policy makers in the administration think it represents the most significant long-term challenge to America's global security.
WHICH events of recent days are likely to have the most significant long-term impact on American business and the economy?
The most significant long-term effect of the building may be that it changed the view Goldman Sachs has of New York.
BP, meanwhile, is proud of its arts sponsorship, calling its sponsorship of the four big national arts organisations "one of the most significant long-term corporate investments in UK arts and culture".
Tuesday's election added a new chapter to what may be the most significant long-term story in New York politics: the breakdown of geographic and ethnic voting blocs whose party allegiances were once bred in the bone.
Since it began in 2000, the Unilever series of annual commissions in Tate Modern's Turbine Hall has become the most significant long-term project instigated by any museum in the early 21st century.
BP, meanwhile, says it is proud of its arts sponsorship, calling its sponsorship of the four organisations "one of the most significant long-term corporate investments in UK arts and culture".
She said the company's support "represents one of the most significant long-term corporate investments in UK arts and culture", and expressed gratitude to BP for its "groundbreaking support of the collection displays and other programmes".
"The rise of these moderate forces, if it is real and sustained, would be the most significant long-term contribution to Israeli national security," argued Gidi Grinstein, the president of the Reut Institute, a think tank.
