Jiang Chen was quite sure about Sumitomo Foundation's influence.
When Celestial Trade chose them as a partner on the Global Power Grid, they were the ones that influenced non-governmental and civil rights organizations to protest and demonstrate at the entrance of the Prime Minister Residence. They were the ones that stated the threats of nuclear power plants, thus indirectly pushed the country's connection into the global grid.
He planned to use the same tactic.
It was difficult to remove the UA military stationed in Nippon through the behind the scene effort of Celestial Trade alone; the situation required a catalyst. A catalyst that would ultimately end the security treaty, as well as turn the UA into a scapegoat. The catalyst had to be convincing, so that it would be difficult for them to prove their innocence, and could even cause suspicion among their allies.