Does God bless nations? Yes. He blessed the nation of Israel. He endowed the Israelites with some special blessings and give them special tasks. God brought His Word and His Son through the people of Israel. Christ was born of the tribe of Judah in the family of David.
Are you the kind of person God can use to be a blessing to your nations? Believers were chosen by God, in Christ, before, the foundation of the world. The Bible tells us that God wants us to be the right kind of citizens.
Be the best citizen you can be. Do so by obeying the Lord, by letting your light shine for Him, by praying for your nation, by sharing His Word with others and by exercising the privileges you have as a citizen of your nation.
God uses people to bless nations, Christians are to be good citizens, the kind of people He can use to strengthen the nation. Be the best citizen and be a witness for Christ.