Absolutely, and luckily it seems Europe is doing just that. Some European countries have made guarantees for Ukraine for economic aid for 10 years. And the aid for 2025 from European countries is doubled compared to 2024.
So the economic side should be pretty good. And more than compensate for USA dropping out completely.

The remaining problem is that Europe doesn’t have the arms storage and production USA has, so that takes longer. But the work has been started.