Answer:
Failure
Explanation:
By only looking at the context clues of debacle, we can infer that word has a negative connotation: something bad happened in Russia that made the officer of the Czar felt that he had not choice but to leave the nation. So, success and celebration are not suitable.
Now, if we look the word in the dictionary, we can find that debacle refers to an event or enterprise that fails, has a breakdown or that ends suddenly and disastrously, often with humiliating consequences. So, debacle can be replaced by failure.
