Iraq Crisis and the US

Iraq is in the state of total chaos. ISIS terrorists have seized major cities like Mosul. Iraq military doesn't look strong enough to eliminate this national threat. Barack Obama announced that he will not be sending any troops to Iraq. Just days after, ISIS terrorists  acquired a major oil refinery in Iraq, which had a significant impact on global oil market, causing oil prices to rise up by 5$ per barrel.
This is not only caused US to panic, but also posed a danger to economies like India, whose government has to pay 8 billion more in subsidy everytime the price rises up by 1$. Although US will not be sending any troops, Obama is sending 300 military advisors to Iraq, to help and train Iraq military to fight against terrorism. And all this is happening because Bush just suspected that Iraq possessed Weapons of Mass Destruction which were never found!
America has to pay a price for all the mistakes they did. Actually they just made a small mistake of electing Bush, which can no longer be called "small". Barack Obama made a very good, appreciable decision of not sending troops to Iraq again, because if he had sent troops, all this would have started all over again. If US invades Iraq again, they'll win war and kill terrorists within few months and just when they'd leave, another similar organization like ISIS would've emerged. Barack Obama made a good decision by ending this cycle.
This is another good reason why we should never start any wars. Because when you start a war, it doesn't end until a long time. Wars appear to end quickly, but only physically. When a government of a loosing nation admits defeat, it doesn't mean that people of that nation don't want to fight anymore. That's what has been happening in Iraq and Afghanistan. US doesn't care about Afghanistan anymore because it doesn't have much oil resources and main goal of it's invasion was to kill Osama. Now that American forces are leaving Afghanistan, people there are concerned about who will save them from attacks of Taliban as well as about maintaining law and order in the country. Even in countries like Pakistan, which have a judicial and police system in well condition, Taliban attacks are pretty common. Afghanistan and Iraq are the nations whose police force have been badly affected by US invasion and thus law and order are in a critical state, which only resulted ISIS. More innocent people, including children, have been killed in these lawless post-war situations.
War is never good. Obama knows this. Obama did not involve US in the Ukraine crisis as well. Russia recently cut off Ukraine's gas supply. The problem is that most of the European countries are dependant on Russia for gas supplies. Countries like Finland, Latvia are 100% dependant on Russia for gas. This prevents EU from imposing strong economical restrictions on Russia. Because of that, Russia is appearing to be winning Ukraine situation. Even though Ukraine has stopped the war from their side, pro-russian militants in eastern parts of Ukraine aren't putting their weapons down.  This war is not only causing innocent people to loose their lives, But this also sends a message to the world, that any country can capture a part of other country and threaten it's sovereignty,independence and still world superpowers like US and EU might not possibly help them. On the other hand, if US had provided military assistance to the Ukraine, the war could've become more violent, causing deaths of more innocent people, including innocent Americans, who couldn't even spot the Ukraine on global map. US has to find a better alternative to war. Putting economical restraints on the countries like Russia certainly isn't working. There has to be a better alternative to war, if there isn't, well we are in serious trouble.