God chose one nation over all other nations is a fact clearly articulated by Scripture:
“The LORD hath chosen thee to be a peculiar people unto Himself, above all the nations that are upon the earth” (Deut 14:2).
God always retains the right to express His sovereignty without the need to justify the decisions He makes.....
God is God and also that God is good (1John 1:5)......His choice to show blessing is entirely His own, as He explained to Moses,.... “I will be gracious to whom I will be gracious, and will show mercy on whom I will show mercy” (Exo 33:19, Rom 9:14-15).
I don't mean this to sound somewhat terse as often happen in my writing but what specifically are you saying? What is the meaning of a "nation". If you are saying the physical nations then, yes, God chooses one nation over another nation all the time. The scriptures teaches us that there were times when God raised up the Babylonians and the Assyrians over Israel just as much as He blessed them.
Somehow people have this romantic sense of Israel that is nowhere to be found in scripture. The nation of Israel, according to scripture, had trouble right from the start when they appointed King Saul (as God warned them they would). King Saul hunted down the innocent David, David (as good as he was after God's own heart) committed murder and adultery, and King Solomon allowed the sacrificing of children to the pagan god Molech. After that Israel and Judah split and at time warred against each other until God wiped them out except for a remnant. And when that remnant reformed they became the Sadducees and Pharasees who our Lord Jesus admonished.
All the nation of Israel serves to show is how much we, as Christians, are like Israel. God chosing, loving and caring for us. We in a state of constant rebellion. We are Israel. This phrase carries much good connotations of God's blessings but it also carries the connotation that we (Christians) are a rebellious and stiff neck people.
If you believe that God favors Israel spiritually then no, He does not. We are the holy nation of God (1 Peter 2:9). God does not bless those who reject His Son but His wrath rest on them.