Can we take it that this would be much the same under President Charles Evans Hughes?
Yes. The realization that the US needed a central bank in the shape of the Federal Reserve system was widespread and support for the creation of the same was broadly bipartisan. Hughes or any other mainstream presidential candidate isn't going to stop the Fed from doing it's job and the Fed is going to control collateral requirements in a manner which will protect the US economy.
Several people have PM'd me asking for book recommendations on this topic. A book recommendation is easy as any introductory macroeconomics text will suffice. I first read about the Fed's management of the Entente loans in an introductory economics course decades ago when they were used to illustrate why the regulation of loans, and especially huge loans, are part of the core business of any central bank.
One recent book on the topic I can point everyone to is
Modern Macroeconomics: Its Origins, Development And Current State by Brian Snowdon and Howard Vane, Edward Elgar Publishing (ISBN 1845422082).
Why should a central bank be inserting itself in the loan process between a bank and a foreign government? It has to do with the two levers a central bank uses to manage a national economy. Those levers are controlling the amount of money in the economy and controlling the speed at which that money can move.
The amount of money in an economy isn't limited only to the physical currency. In fact the amount of physical currency is only a fraction of the amount of money in an economy. The valuation of goods and services and the balances held in financial instruments, for example, use a "virtual" currency of sorts. Your bank doesn't have the physical cash on hand to cover the amount of money being held in it's customers' checking and savings accounts. Similarly, when you took out a loan to buy your car or house, the bank which gave you the loan didn't hand over a bag of physical cash to the seller of the car or house.
This means a lot of a nation's currency exists only on spreadsheets and in ledgers. It's "virtual" to borrow another phrase and a central bank needs to keep control over the creation of this "virtual" currency just as it controls the presses and dies creating physical currency. In fact, because there's is much more of this "virtual" currency sloshing between spreadsheets and ledgers than "physical" currency sloshing between wallets and cash registers, a central bank needs to exercise more control over the creation of "virtual" currency.
When money is created, whether "physical" or "virtual", the speed at which it enters the economy and the speed at which it moves through an economy become a concern. Almost all loans are small enough not to flood an economy, but huge loans - and the loans to the Entente powers were huge - can create significant problems with the manner and speed they enter an economy.
Think of a bucket of water slowly draining through a small hole in it's bottom. We can keep the bucket full by pouring in an amount of water equal to the amount draining. We can also dump in a huge amount of water, much more water than the bucket-hole system can handle, and watch the system fail. It was like that with the Entente loans. Once a loan was granted, the Entente powers still faced restrictions on how fast they could use the line of credit created. The "capacity" of a given market determined how much credit an Entente power could "dump" into that market. This was in the best interests of both the US and the Entente powers.
If Britain, for example, entered the dried pea market with 100 million dollars, the price of peas would quickly skyrocket to soak up all that money. That would be bad for the US economy as too many farmers would begin planting nothing but peas in the hopes they could sell them for the new obscene price. That would also be bad for Britain as they'd be paying far too much money for far too few peas. Britain would take it's next round of pea money to a market where it could get a better price and the US would be stuck with a pea glut.
In order to avoid problems like this, the Federal Reserve regulated the speed at which the Entente powers could access the lines of credit their war loans created.
When you stop to think about it, the larger the loan, the larger the amount of "virtual" currency created, the larger the effect on the economy, and the larger the need for a central bank to control the situation. When the Entente powers approached the US credit markets for huge loans, the size of those loans and their potential effect on the US economy made it the duty of the Federal Reserve to regulate how those loans were drawn up and spent.
So, this wasn't a case of the Fed intervening and assisting the Entente powers is raising loans in the US credit market and then spending those loaned funds within the US economy. It was a case of the Fed regulating the creation of "virtual" currency through loans and regulating the speed at which that new "virtual" currency entered the economy.
Loan regulations like collateral requirements are one method of controlling the creation of that "virtual" currency, controlling how it enters an economy, and controlling how fast it can move through an economy. When the Fed regulated loans from US banks to the Entente powers, it was the Fed doing it's job and not, as some want to believe, the US government making a political statement or stating a political preference.
Stating a political preference through economic policies would come later when the US entered the war and the US government loaned the Entente governments money directly and outside of the normal credit markets.