US: Announces replacement for aging Hubble in 1996. Fails first project and downsizes in 2002. Spends 20 years pushing the project back 2-3 years. Finally launches in 2021.
China: Announces project in 2016, with launch planned for 2021. Setback to 2023-24. 8 years.
I wouldn’t celebrate before having the thing actually in orbit though. I’m confident they will succeed but let’s wait two years before bragging about it