But as far as what this is supposed to be about a Strategy For Peace, looking at it from a Liberal Internationalist perspective the policy for achieving that I believe is fairly simple. Harder to execute and perhaps even harder to get passed. But at risk of quoting Ronald Reagan, you do that by being strong at home. You don't waste tax dollars on the military, but you're strong enough to the point both militarily and economically that another country would be crazy to want to attack you, or attack one of your embassies oversees. Because they know you could either destroy them militarily, take out their current regime, or economically bankrupt you, or a combination of all of those things.
Instead of trying to police the world by yourself, or taking our regimes simply because you don't like them, (2003 Iraq War comes to mind) you work with your allies to keep potentially dangerous, or dangerous regimes at bay and in a box. You work with the people on the ground who you can work with in those states to see if they can knock the current regime out of power. You also incentivize those rogue states to improve their behavior. To not be so authoritarian with their own people. To not invade other states, to not fund terrorists. And you work with your allies so these rogue states don't become so strong that they become such a problem that a military option could never be on the table.
A lesson from the Vietnam War and the Iraq War. Don't attack and invade countries that aren't threats to you. Don't try to fight for people who aren't willing to fight for themselves. Some countries are destined to fail and fall simply because the people there aren't willing to do what it takes to see that their country can succeed, or at least become stable. And that is when you sort of have to let nature take its course. Even if that means a new authoritarian regime that you don't like comes to power there. Like the Communists in Vietnam. We stayed out of Cuba for the most part at least during their civil war and we should've done the same thing in Vietnam and perhaps Korea as well.
Peace is not easy which means it is not easy to achieve. America has its own experience with their own civil war when the Unionists won the battles and the war. But where the Confederates won the aftermath and whatever peace that both sides were able to achieve. With the brutality that the Confederates were able to get way with against the former African slaves. But you can achieve peace when you don't try to do everything yourself. You play your part and allow and demand that your allies do the same thing. You live by the standards and human rights that you say you want for the rest of the world in your own country. And you're strong enough to make it clear that it would dangerous if not suicidal to try to attack you.