Trump’s current war on Iran picks up where a longstanding enmity left off

The mutual resentments that have fueled tensions between the US and Iran have simmered for nearly half a century

For millions of younger Americans, the sudden explosion of Iran onto the national political stage and consciousness may seem like a bolt from the blue.

Yet for older generations and those with deeper historical awareness, Donald Trump's announcement on Saturday of strikes against a distant foe is more like the outcome of a collision long foretold.