The 1962 war was a major setback, thereafter, be it in 1967 (Cho La Incident) or the skirmish in 1987, china has always provoked border issues seeing the development by the Indian side on the borders.
This makes china vulnerable to such an extent that while the world was busy making out against the pandemic, they were busy with their territorial lust worldwide.
South China Sea is also a witness although under deep watch by the USA.