I pray that the U.S. NEVER turns against Israel!
But the evangelical Christians in the USA with their misguided understanding of the end Time Prophecies concerning Israel and where she should be so that the End Times can roll on have been the ones setting the USA's government policy concerning Israel and the Middle East. As such the USA government has been promoting policies that are contrary to what God is going to do when the two ages of God walking contrary to Israel is over and Israel begins to repent of her continual idolatrous worship over the past four ages such that God will hear their cries and turn once more towards them.
When Satan is judged and imprisoned in the Bottomless pit, Israel will, in the words of Christ, send a delegation off to declare that they no longer want Satan to the king over them. When The Israelites in Jerusalem see the judgement of the Kings of the earth assembled at Armageddon by Christ, they will send a delegation to Him and seek His terms of peace. Both of these prophecies can be found in Luke 14 and 19.
In Jeremiah 50 the second king of the north, who is the president of the USA, lead a coalition of nations to enter the Land of the Chaldeans, i.e. Iraq, and instead of destroying the Land of Babylon, this coalition of nations set about healing the land of Babylon by the introduction of "democracy" in the land of Iraq because of the oil within its boundaries.
When God then sent the Persians to destroy the Land of Babylon the USA and many from the coalition of nations opposed God and attacked the Persian representative, i.e. IS, who had gone into the Land of Babylon to destroy it.
The USA and the other kings of the Coalition of Nations went against God and acted God like and now God is bringing against all of these Nation His wrath in the form of Climate Change, Locusts and Pestilence as signs for these nations that they have sinned by what they have done in Iraq.
Now it is too late to pray that the U.S.A. will never turn against Israel.
It is better if we Christian would humble ourselves and repent of our turning away from God to act God like in the things that we have all done with regards to Israel and the Middle East in our own selfish self interests.
If enough "Christians" humble themselves and repents of our iniquities, then perhaps God will hear our prayers and His wrath against us will subside and He will look on us with favour.
Remember that all of the Kings assembled at Armageddon are there because of what they have done to the Israelites over the centauries from when God finally kicked them out of the Land of Canaan up and until the present time as they sheltered within our respective lands. Our respective nations are just as guilty of mistreating the Israelites as any of the other nations that will also assemble there on the Great Day of the Lord.
Shalom