Donald Trump has boxed himself in by promising to 'help' Iran's protesters. But he has few good options.

US president gives clearest signal yet that he might take military action against Tehran over killing of demonstrators

As US president tells protesters ‘help is on the way’, any military action would be unlikely to succeed

Trump told Iranian protesters that 'help is on its way' in a Truth Social post.

From Venezuela and Iran, Trump has attacked countries in the past when diplomacy appeared to be working.

Donald Trump has boxed himself in by promising to 'help' Iran's protesters. But he has few good options.

Despite Iran's vulnerable position, any US strikes could risk triggering a protracted conflict, analysts say.