I have heard it said that Isaiah 9:10 is referring to America, but I am still not convinced of that. However, the verses do show the pride of those nations God has destroyed or will destroy because they think they can "build back better:"
"9 And all the people shall know, even Ephraim and the inhabitant of Samaria, that say in the pride and stoutness of heart,
10 The bricks are fallen down, but we will build with hewn stones: the sycomores are cut down, but we will change them into cedars."
This is what I think of whenever a politician says "build back better." God will destroy the nations for their wickedness and pride. Those that think they can build it again better than before are wrong. Just like you said Annalise, they will be destroyed for rejecting God.
Hosea 4:6 - My people are destroyed for lack of knowledge: because thou hast rejected knowledge, I will also reject thee, that thou shalt be no priest to me: seeing thou hast forgotten the law of thy God, I will also forget thy children.
I think everything currently happening is just showing us that God has already turned away from America.
I also think you are correct about the meaning of "in that day." It might even include whatever is about to happen.
And in that day shall ye say, Praise the LORD, call upon his name, declare his doings among the people, make mention that his name is exalted. Isaiah 12:4
Many will say to me in that day, Lord, Lord, have we not prophesied in thy name? and in thy name have cast out devils? and in thy name done many wonderful works? Matthew 7:22
But of that day and hour knoweth no man, no, not the angels of heaven, but my Father only. Matthew 24:36
These all refer to the future. We have not seen them happen yet.