It’s not hard to read the mood of the electorate and capitalize on it.
Now, may they secretly be rejoicing the outcome? If that were the case then #NeverTrump would have been formed, nor would they continue. In addition there would be immediate support for Trump from the likes of the Bushes, and Ryan.
But you have to ask how the U. S. defaulting aides them in any significant manner. If anything it would aide the Democrats, even though they have played a major part along with Republicans because the blame would be pushed by the press that if was exclusively the Republicans.