Gao Yang didn't have clairvoyance, nor did he have acute hearing, so all that had happened was deduced through speculation, which means they could only guess what America was planning.
Now, through Hunter, speculation has become reality, and reality is even more exaggerated and perilous than the speculation.
What did Hunter say? Grand Ivan must die because America absolutely does not want another 911 event. This statement is not just offhand - it is very significant. What does this imply? It implies that Grand Ivan not only has the capability to harm America but that he is very likely already taking action, and America is making every effort to prevent this.
The more attentive America is, the more difficult Grand Ivan's situation becomes. The trouble is that Grand Ivan could still handle the pressure, but now it's Gao Yang, with his small shoulders, who is bearing this heavy burden for Grand Ivan. What does it mean to be under great pressure? This is it.