The "quality" of Christians is not the point. Since it is God alone who numbers His flock the size of that flock is in His hands.
But the trend is certainly positive. From 12 to two billion. Out of two billion Christians, there are undoubtedly men and women who are faithful to Christ alone.
And that number most certainly is more than 12.
I just don't get the attitude of those who cavalierly dismiss two billion Christians as insufficient evidence for the success of the Gospel. Peripherally and no doubt unknowingly, they are doing the work of the enemy by admitting defeat.
"Finally, brethren, pray for us, that the word of the Lord may have free course, and be glorified, even as it is with you" -- 2 Thess. 3:1
"So mightily grew the word of God and prevailed." -- Acts 19:20"So shall my word be that goeth forth out of my mouth: it shall not return unto me void, but it shall accomplish that which I please, and it shall prosper in the thing whereto I sent it." -- Isaiah 55:11
Where in Scripture does it say the word of God does not "prevail" but instead fails?
From a geopolitical standpoint, and from a sense of obligation for the genocide of the Jews in WWII, Israel must be protected and defended. But as far as Scripture goes, dirt and rocks and vain genealogies mean nothing to God. "Neither Jew nor Greek; all one in Christ Jesus." -- Galatians 3:28
Unless, of course, those dirt and rocks and "vain" genealogies are an integral part of the promises made to the nation of Israel that God has yet to fulfill.