Definition of "air cover"

But if the Government really wants our railway to reduce the level of its subsidy and improve value for taxpayers' money, then it must provide the political air cover to enable managers to get on and make the hard decisions that are needed... and then see them through.

2022 January 12, Sir Michael Holden, “Reform of the workforce or death by a thousand cuts?”, in RAIL, number 948, page 25