The decision facing the U.S. government regarding the current outbreak of greater violence in the Middle East is unusually difficult.

Before the murderous fanatics of the Islamic State showed more force than anyone had foreseen, President Obama, and Ameircan public opinion, was sensibly inclined to take no action whatsoever. That was based on the correct understanding that the internal political workings of neither Iraq nor Syria were in any significant way relevant to American national security and that as the disastrous invasion of Iraq by President Bush demonstrated, efforts to bring about changes to those regimes would do more harm than good.

But the horror felt by civilized people at the aggressive, triumphant, butchery by the Islamic State has changed the situation. American intervention to keep these fanatics from genocidal attacks on people of different religions and ethnicities was broadly supported here and elsewhere.

That support was entirely justified; however, it is important to make clear on what it should be based. American public opinion opposed to military intervention underwent a substantial change, but this represented a recognition that as a civilized nation we had an obligation to stand between these murderers and their intended victims, to the extent that we could; it was not – and should not have been – acceptance of the view that they threaten the United States.

The distinction between intervening to stop the most evil force currently operating in the world from perpetrating its horrors and stepping in to promote stability in the Middle East because that is in America’s national security interest is essential to making the correct decision about what we should be doing.

To the extent that we can use American air power to diminish the capacity of the Islamic State to engage in mass murder motivated by ethnic and religious hatred, we are morally obligated to do so. But first the president should drop his unconstitutional, undemocratic argument that resolutions passed more than 10 years ago in response to al-Qaida gave him the authority to make war in Syria with no further Congressional authorization.

The president has the inherent authority to respond to attacks on American national security, but to undertake a discretionary military action, even one as strongly justified morally as killing the killers, should not go forward in our society without the broadest possible participation of those elected to make decisions. I am particularly puzzled by the notion that the president needed authority to provide weapons to the moderate Syrian opposition but is entitled to bomb a foreign country – again even for very good reasons – on his own.

The argument that American national security depends on there being an overthrow of the Assad regime, and greater stability and harmony in Iraq is wrong. I very much disapprove of Assad’s method of governing, but he and his father before him had run Syria for decades without anyone making the plausible argument that they threatened American security. And it is now very clear that Bush’s invasion of Iraq may have made things worse from the security standpoint, and certainly did not improve the situation.

The fact that our national security does not in any significant way depend on the nature of the regimes in Syria and Iraq is fortunate, since our experience in Iraq and the realities in Syria make it clear that there is very little we could do about this if we had to. It is certainly also the case that attempting that in either country would be enormously expensive.

At the very least, no one should be allowed to argue for that without being challenged as to how they will pay for it.

I acknowledge that the policy of America using air power to kill the killers carries with it no guarantee of success. But that is the point. Limiting the policy choices to either actions that guarantee success or doing nothing at all is an inappropriate way to decide tough issues.

The appropriate moral course for the United States is to use our air power to diminish where we can the ability of the Islamic State to butcher innocent people. I was asked on a television show why I advocated doing that but disagreed that we should be actively intervening to overthrow Assad, who has also been guilty of human rights violations. The answer is that it is important to recognized gradations of evil. Assad is a ruler who has engaged in massive violations of human rights to stay in power but as bad as he has been, the Islamic State is worse. These are people who kill ruthlessly because of their hatred for people who differ with them ethnically or religiously, and they are seeking not to maintain control in any one are, but in fact to extend it indefinitely. It is not that Assad is better than they are; it is that they are far worse than he is. And to repeat my central point, the fact that we cannot eradicate all evil does not mean that we should do nothing at all. It is not clear that there are sufficient forces in Iraq and Syria to defeat the Islamic State murderers. That is a sad fact that cannot be overcome by American troops. But it is also the case that American air power – along with Sunni Arab allies can help those anti-Islamic State forces that do exist.

I hope the president will ask Congress for the authority to use force against the Islamic State, and that Congress will vote in favor of doing the best that we can in this difficult situation.

Barney Frank is a retired congressman and the author of landmark legislation. He divides his time between Maine and Massachusetts. Follow him on Twitter: @BarneyFrank

— Special to the Telegram