In The Folly of World War IV: Wars Are Never Quick, Cheap or Easy Moyers & Company 12/04/2015, he gives some realistic cautions on the decisions of the NATO countries including the US and Germany to escalate militarily in Iraq and Syria without any coherent political strategy and without enough forces to pacify the area. And, yes, I use "pacify" to recall the Vietnam War. And Bacevich speculates on the tremendous effort and costs a serious attempt to do that would involve.
In 1991, when the first President Bush ejected Saddam Hussein’s army from Kuwait, Americans rejoiced, believing that they had won a decisive victory. A decade later, the younger Bush seemingly outdid his father by toppling the Taliban in Afghanistan and then making short work of Saddam himself — a liberation twofer achieved in less time than it takes Americans to choose a president. After the passage of another decade, Barack Obama got into the liberation act, overthrowing the Libyan dictator Muammar Gaddafi in what appeared to be a tidy air intervention with a clean outcome. As Secretary of State Hillary Clinton memorably put it, “We came, we saw, he died.” End of story.
In fact, subsequent events in each case mocked early claims of success or outright victory. Unanticipated consequences and complications abounded. “Liberation” turned out to be a prelude to chronic violence and upheaval.
Indeed, the very existence of the Islamic State (ISIS) today renders a definitive verdict on the Iraq wars over which the Presidents Bush presided, each abetted by a Democratic successor. A de facto collaboration of four successive administrations succeeded in reducing Iraq to what it is today: a dysfunctional quasi-state unable to control its borders or territory while serving as a magnet and inspiration for terrorists.
Stephen Biddle and Jacob Shapiro make a similar point in Here’s why we can only contain the Islamic State, not bomb it back to the Stone Age Washington Post 12/01/2015:
More than a decade of continuous warfare against militants in Afghanistan, Iraq, Libya and elsewhere have taught us a great deal about what works, what doesn’t, and why. And that experience suggests that to defeat the Islamic State — defined as eliminating its ability to carry out Paris-style terrorism — would require a vastly greater effort than almost anyone now proposes, and a vastly greater effort than the American public is likely to support.I wish our policymakers would take these realistic lessons from recent experience seriously:
In practical terms, what’s possible against the Islamic State is some form of containment or suppression. And that’s essentially what the administration’s current policy amounts to. You can quibble with elements of that policy, but we’re stuck with its basic outline. The Western interests at stake are limited; the underlying problem is deeper and tougher than critics imply, and the cost to solve the real problem is much higher.
If the 2003 Iraq campaign, the 2001-2 Afghan campaign, or the 2011 Libya campaign tell us anything, it is that taking the enemy’s capital does not reliably end the war. Replacing a hostile regime with a weak successor in a splintered society or, worse, catalyzing anarchy, simply launches the war’s next phase: insurgency and civil conflict.
The resulting chaos is often little better for U.S. interests than what came before.
The Islamic State itself has now established local affiliates in unstable post-Moammar Gaddafi Libya and in ill-governed parts of eastern Afghanistan. Its predecessor, al-Qaeda in Iraq (AQI), got its start in the security vacuum of post-Saddam Hussein Iraq. Many other militant groups hostile to Western interests have exploited the same disorder in these and other war zones.