Isaiah 18:7
"At that time gifts will be brought to the Lord Almighty from a people tall and smooth skinned, from a people feared far and wide, an aggressive nation of strange speech, whose land is divided by rivers - the gifts will be brought to Mount Zion, the place of the Name of the Lord Almighty." NIV translation
In 2 Chronicles 32:23, we are told that people brought gifts to Hezekiah after the defeat of the Assyrians. In this, we see that God's timing was perfect to accomplish His purpose of drawing men to Him.
The same thing will happen throughout the time of the great tribulation described in Revelation. God will allow the devil to build his kingdom on the earth only to see it quickly destroyed by the very hand of God. This, too, is God calling people to Himself through a demonstration of His power.