No allies? I would have hoped that you didn’t forget about the Hessians.
Washington, being an intelligent and precision-thinking man, would have certainly taken US industrial and military strength, vastly superior to what he had available over 130 years earlier, into account, as well as the imperialistic belligerence of the Kaiser. The Lusitania would have been the last straw. Remember, neutrality is a two-way street, not the cowering before bullies.
You mean the Lusitania, that was carrying about 173 tons of war munitions for Britain? That Lusitania?
The king's use of foreigners against his own subjects in 1775 was something that caused a lot of his formerly loyal subjects in America to start to consider renouncing their allegiance to the king (along with his proclamation effectively removing them from his protection, his contemptuous reaction to the Olive Branch petition, and Lord Dunmore incitement of the slaves to rebellion).