我们已经尽力做到防范于未然。

We had tried to take precautions.

与其补救于已然，不如防范于未然。

To forestall is better than to amend.; Prevention is better than cure.

虽然北朝下一步举动未然可知，但如果金宽镇授权空袭，（朝鲜半岛）的紧张局面会进一步恶化。

If air strikes were authorized by Kim Kwan-jin, the likelihood of further escalation would certainly be higher, though what the North Korean response would be remains anyone's guess.