The long-awaited trade deal between the U.S. and Japan has investors celebrating after months of uncertainty. But as the song goes, nagging questions always remain.

Who is going to buy the "cars, SUVs and trucks” that U.S. President Donald Trump has promised to sell? Who is going to purchase the 100 Boeing jets? And what possible structure could the $550 billion fund, allegedly financed by Tokyo with 90% of profits going to U.S., actually take?

Answers are sorely needed, not just because of an already growing comprehension gap between the countries over what was actually agreed, but to inform South Korea, the European Union and other close U.S. allies who are trying to wrap up similar deals before Aug. 1.