I woke up with "Battle of New Orleans" in my head, so I'll ask.

[The Magistrate]

4. Regarding The First, Sir

It was the appearance of strong French forces in the field, on land and on sea, signaling the possibility the matter could escalate to a grand conflict with a major power, that seems to have been the deciding factor.

In regard to the second, a desire for peace after the great strain of the Napoleonic Wars was certainly a factor in the English decision to settle with the United States, rather settling it once and for all. But commerce raiding by privateers under letter of marque from the United States did cost England a good deal. Insurance rates for merchant voyages verged on the prohibitive by 1815, and these privateers accomplished a good deal more than Napoleon's naval forces ever managed.