What does "strong" means?
1.
----In 2015, the U.S.-China Strong Foundation launched the “1 Million Strong” initiative, seeking to increase the number of American students studying Mandarin to 1 million by 2020. ----
2.
The US-China Strong Foundation is a nonprofit organization that seeks to strengthen US-China relations by investing in a new generation of leaders who have the knowledge and skills to engage with China.

Question

What does "strong" means?
1.
----In 2015, the U.S.-China Strong Foundation launched the “1 Million Strong” initiative, seeking to increase the number of American students studying Mandarin to 1 million by 2020. ----
2. 
The US-China Strong Foundation is a nonprofit organization that seeks to strengthen US-China relations by investing in a new generation of leaders who have the knowledge and skills to engage with China.

Answer

Hi

The word 'strong' means the opposite of weak. So for example "A strong person can lift a heavy weight, or cope with a difficult situation." - the first being physical strength and the second being emotional.

However, 'strong' is often used in phrases that signify a big number. In this case 'a million'.

So 'A Million Strong' means both a big number and an organisation which is resilient, partly because of the big number of people.

Answer

https://www.oxfordlearnersdictionaries.com/definition/english/strong?q=strong

​used after numbers to show the size of a group
a 5 000-strong crowd
The crowd was 5 000 strong.