The angel announcement was "and on earth peace, good will toward men". At least that is the King James translation. Modern translations get it right, "peace among men with whom He is pleased." But even this needs a little explanation.
So many of our Christmas Carols were written when musicians had only the King James version to guide them, and so we are overwhelmed with the wrong message this time each year. It seems as though the birth of the Messiah was supposed to begin a universal reign of peace. In fact that is true, but not the way most people suppose. The Jewish conservative commentator, Dennis Prager, claims that is the biggest reason why he cannot consider Jesus to be the Messiah. After his birth there has not been an advent of world peace.
The word translated "good will" in the KJV is used elsewhere in the New Testament, and it always seems to refer to God's sovereign good pleasure. He is called the one who works all things after the counsel of his will (Ephesians 1:11).
For example, the word occurs in Matthew 11:26, "Yes, Father, for such was your gracious will." (ESV) In context Jesus is referring to God's hiding certain ideas from some people and revealing them to others. This was according to the sovereign good pleasure of God. In Luke 12:32 Jesus says to His disciples, "Fear not, little flock, for it is your Father's good pleasure to give you the kingdom."
Galatians 1:15 is another instance of the use of this word. Here too it is all of God's good pleasure, and not of Paul's choosing that he was called to be an apostle. Again it refers to the sovereign, unconditioned determination of God.
You see what the angels were saying (singing?) to the shepherds that night was that God was giving peace to many people, namely all those who were beneficiaries of His sovereign good pleasure. Why this is not grasped by many is simply the fact that this pleasure is a subset of election. And those who assume that God's grace must be egalitarian despise the doctrine of election. Never mind that it is clearly taught in the Bible, it's not politically correct to favor one over another, and therefore it must mean something else.
I wonder what kind of a problem these same people may have with the fact that it is God who allows one soul to be born to an atheist family in the Czech Republic, and another soul to be born to a wholesome Christian family in the United States. While it may be true that your birth family does not determine your salvation, no one can doubt that there is enormous spiritual advantage for the one over against the other. This is only one obvious form of election. Continue to check the context of Matthew 11 and you will see that Jesus is thanking His Father for election. "I thank you, Father, for hiding these things from the wise and prudent." Ponder that a moment. God has hidden insight from cocky know-it-alls. "And for revealing them to babes." That is, for revealing these same things to those who are beginners in the Christian life. That's simply election at work.
In God's sovereign disposition he has given this earth shattering news of Messiah's birth to lowly pungent savored shepherds. They will derive the peace of God that lasts forever from this announcement. Glory to God in the highest! Indeed we must do that still. That is our purpose when we gather for public worship. To God alone be the glory. And peace--His peace--rests upon all those who put their faith in the Son He gave to be our Savior. It's not universal world peace. But that will come when Jesus returns. Be patient.