Question:
You believe that she deliberately went back?

Does it follow that "She didn't go back on accident, did she?"?
Answer:
no

Question:
Right now about two dozen countries are suspected of pursuing chemical-weapons programs, and they do so with impunity.

Does it follow that "China has a chemical weapons program."?
Answer:
it is not possible to tell

Question:
The clothes didn't fit.

Does it follow that "The clothes fit perfectly."?
Answer:
no

Question:
No, indeed.

Does it follow that "Not even a chance of it."?
Answer:
it is not possible to tell