Yes, God still judges nations for their sins just as He still judges individuals. The Bible is clear: "You may be sure that your sin will find you out" (Numbers 32:23).
After all, God hasn't changed over the centuries; He is holy and pure, and whenever we scorn Him, we run the risk of incurring His judgment. Sin is an offense to Him and the reason is because sin is a deliberate denial of God and His will for our lives. When we sin, we deliberately turn our backs on God and say our way is better than His. But we are wrong and eventually we will pay the price. The Bible warns that "the wages of sin is death" (Romans 6:23).
The same is true of a nation that rejects God. When ancient Israel turned against God, the prophets warned that God's judgment would eventually come upon them and it did. But God also warned that the surrounding nations would be judged too because they had no regard for God and they were. Sometimes it happens in one great catastrophe; sometimes it happens in a series of smaller disasters and defeats. But it happens.
How long can a nation scorn God before He brings judgment upon them? Only God knows the answer but His patience has its limits. Pray for our nation, that God will bring us back to Himself before it is too late and let it begin with you, as you turn to Christ in repentance and faith.