Amb.Blackwell was one of the effective diplomats in the region. In the past the leverage and pressure US could bring upon Pakistan's military and civilian governments were quite significant and was used effectively to ensure Pakistan does not escalate misadventures beyond a point where Indian assertiveness obligated military action. While the $ aid leverage still exists, Pakistan's alliance assumptions have reversed especially in view of the emerging US-India relationships. Therefore the 'Cease and desist' command will have to come not from DC but perhaps Beijing which is what Pakistan now sees as the next natural recourse.
It us true that Modi's mandate and personality indicate faster military action should a misadventure be traced to Pakistani state agencies.
Fortunately recent border action-reaction sequences indicate Pakistan is indeed compliant to China's C&D, so IMO the probability of such Pakistani misadventure is negligible.