By Mark Stone, US correspondent
Some context on this B-2 movement - which is all caveated by the fact that we really don't quite know what is going on.
They have left their home base in Missouri and are heading west to the Pacific region, not east to the Middle East. They are heading to Guam.
It's possible they could then continue that way round the world and end up in the Middle East / CENTCOM area of operations. The Pentagon has referred all inquiries to the White House.
It's also logical for the US to want to maintain a show of force in the Asia-Pacific region to counter any Chinese assumption that America is distracted.
Remember that Donald Trump has already authorised the redeployment of the Nimitz Carrier Strike Group out of the Pacific region last week to bolster military force in the Middle East. The USS Nimitz aircraft carrier and its fleet had been deployed to Asia.
In the context of countering Chinese expansionist desires, vis a vis Taiwan, the Iran crisis presents immediate military logistical challenges for the US given that its military might is in the Middle East.
But it also presents America with longer term strategic challenges - China is watching how America responds in Iran.
The calls for America not to get involved in another foreign war are encouraging for a Chinese leadership with eyes on Taiwan.