The phrase "a potential enemy" is correct and usable in written English.
It can be used when discussing someone or something that could become an adversary or opponent in the future.
Example: "In times of conflict, it's important to identify a potential enemy before making strategic decisions."
Alternatives: "a possible adversary" or "a likely foe."
Everyone is a potential enemy.
At the same time, the former rebels treated nearly every man as a potential enemy.
The policy appears to treat missile defenses as another way of sowing doubt in the minds of a potential enemy.
"We have to have responses that are going to be known to us and not a potential enemy," he said.
Their main worry was not a potential enemy of the United States, but one of America's closest friends.
Here everyone is a potential enemy until proven otherwise, and an ID card is essential to go anywhere.
A strategic oil reserve would provide a visible deterrent to any potential enemy that might consider China's economy incapable of sustaining conflict.
The Mongols remained a strong potential enemy of China for the next century, and the Genghis Khan clan in Mongolia continued to regard itself as the legitimate ruler of China.
It is clear that Netanyahu wants to preserve the status quo, even if it means that Israel reverts to a position where every one of its neighbors is an actual or potential enemy, even if it means that its strategic relationship with Turkey is over, even if it means that it has no one in the region to help prevent war with Iran.
"Iran's credible mining threat can be an effective deterrent to potential enemy forces," an unclassified report by the Office of Naval Intelligence, the American Navy's intelligence arm, concluded in 2009.
Indeed, what security does NATO offer vis-a-vis Russia (not an official or even potential enemy, of course) when half of Western Europe is desperately dependent on Russian oil and gas?
