Richard Moore, the chief of British secret intelligence service MI6, is concerned that China could make a "miscalculation" because it is overconfident.
A report from the Office of the Director of National Intelligence warns "climate change will increasingly exacerbate risks to U.S. national security interests."
Omicron symptoms could be mild, according to the South African doctor who first spotted the variant, now dubbed "of concern" by the World Health Organization.
Biden ordered precautionary restrictions on travel from South Africa and other countries after fears of the omicron Covid variant spurred a stock sell off.
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