Yes, I'm assuming the 1916 programme continues; since to posit a war with Britain, it's necessary. I will also ask how Britain affords a response. Eating their shoes, perhaps?
I can think of a number of ways of finding funds. Countries can be very productive when properly motivated. As they can be recklessly careless at time. The US easily had the capacity to fund the 1916 programme but it was struggling to get funding through Congress, even while the Japanese were building their response and Britain was developing markedly more powerful ships.
Britain ends up starving as America simply refuses to trade with it and makes convoys from Argentina... risky.
So highly protectionist America, as a result with a trade imbalance with Britain, cuts its own throat by refusing to sell to Britain. This hurts the British economy how?
Interfering with international trade is an act of war so presuming the last section is talking about the situation in a war. From which point would the USN operate against convoys from Argentina? Operating at a range of several thousand miles against defended convoys with nearby bases is not going to be easy, no matter what form of attack is made. [I presume that you are thinking mainly of submarines attacks on such supply lines? Don't also forget that the USN, having committed itself to a hugely expensive battleship programme could have difficultly arguing for a major sub construction programme. Not to mention that there could be difficulties in that the submarine was widely seen as defeated in WWI and it was to stop unrestricted sub attacks, which the US decried as an attrocity that the US went to war in WWI.]
Steve