Why didn't the USA build ships, manufacture cannons, Henry repeating rifles and military wagons and supply them, and horses to the irish?

In the 1840s and 1850s and 1860s ?

Greg2021-03-02T01:26:38Z

Because back then America was isolationist.

Elaine M2021-02-25T15:30:59Z

It coincided with the American Civil War being fought here. 

Anonymous2021-02-25T04:12:12Z

the Royal Navy even after WW2 untill 911 the Royal navy was taking ships full of Guns ammunition and explosives

and after 911 the Irish Americans stopped supplying and Supporting Baby Killers

L. E. Gant2021-02-25T03:09:32Z

It did. Commerce is commerce, and they were carpetbaggers trying to make a profit from any suffering soul willing to pay for their goods.