There is no such community as "the world".
The planet is inhabited by mutually incompatible races, tribes, and nations, who normally settle their issues by violence fueled by hatred and blood lust.
But, to the extent that an imaginary "world community" exists, one common bond it could have would be anti-semitism, so you wouldn't expect its members to give a flying f*** if Israel were attacked, since 1948 or since 1948 B.C., for that matter.
Israel's ally and defender is the G-d of Abraham, not some imaginary "world community".