Can peace really be attained after war?

no, what is peace when there is war? I believe that war is out of greediness and pettiness and war should not have happened at all.

Historically, enemies can become friends, following a war. For example, in WW II, the US fought against what were then known as the Axis powers, Germany, Japan, and Italy. This was an extremely bitter war, with tremendous violence and hatred and millions of deaths. The US even used the atomic bomb against Japan, which so far is the only time in history that the atomic bomb has been used in war. However, following WW II, the US became very good friends with all three of its former enemies, and no new hostilities are expected. I could also point out that the most bitter conflict of all, during WW II, was between Germany and France, and yet now these two countries are both members of the European Union and are very close friends who, we can reasonably predict, will never again have reason to go to war with each other. So yes, peace can be attained after war. It is not impossible.