Back in 2003, a U.S. president used unsubstantiated (and as it turned out, false) claims about WMD programs in Iraq to launch a war that wrecked Iraq, killed hundreds of thousands of Iraqis, and cost the U.S. taxpayer well over $1 trillion — and counting. On December 29, a U.S. president launched a large-scale air-raid against five bases along the Iraqi-Syrian border run by Ketaeb Hizbollah (KH), an Iraqi militia allied with government forces. U.S. officials claimed that KH was responsible for an attack that two days earlier killed a U.S. contractor in Kirkuk, 400 miles east of the KH bases on the Syrian border. But they did not see the need to produce any evidence of the KH’s responsibility.

The December 29 raid killed at least two dozen people — members of KH and the Iraqi security forces — and has brought the U.S. to the brink of a new war in Iraq or even of an outright confrontation with Iran, seen in Washington as being KH’s main backers. The consequences of any such escalation, while unforeseeable in detail, would certainly be disastrous for Americans, Iraqis, and numerous others.

Can escalation be prevented?

As of today (January 1), the prospects look grim. Yesterday, the funeral cortege for the slain fighters reached Baghdad, and enraged KH supporters (and leaders) mobbed the U.S. embassy compound, storming through its outer perimeter and besieging those inside. Overnight, scores of additional Marines were airlifted into the embassy’s inner redoubt as Washington announced the dispatch of an additional 500 U.S. troops to join the 5,000 troops (and a similar number of military contractors) already in the country. This morning it looks as if the KH supporters have left the embassy compound.

Behind all the military fireworks, the engines really driving the prospects for war or peace in Iraq still lie, as Clausewitz reminds us, in the realm of politics. And not just — or perhaps, not even mainly — in the realm of American politics, though the “Wag the Dog” possibilities for the year ahead are substantial. But the politics within Iraq and the global system are also potent factors.

Inside Iraq, the country’s people are still reeling from the numerous shocks of the past 40 years: a hugely draining but ultimately unsuccessful war effort against Iran; the disastrous aftermath of Saddam’s invasion of Kuwait; 13 years of crippling UN sanctions; the U.S. invasion and takeover of the country and its subsequent dismantling of all organs of the Iraqi state; the apocalyptic eruption of ISIS in 2014, and so on. Under all these shocks, a once proud and well-educated citizenry has become impoverished, resentful, volatile.

Over the past few months, much of the resentment of the populous, predominantly Shiite-Arab south had been turned against Iran, a neighbor that had welcomed Washington’s overthrow of Saddam, had later built a substantial presence in Baghdad and the south — and had cooperated closely with Washington, the Iraqi government, and the Iraqi Shiite militias in their joint campaign against ISIS.

For months now, large-scale protests have rocked Baghdad and cities to the south, calling for the overthrow of “the regime.” Protesters torched several Iranian government outposts in key southern cities. Last month, under the pressure of this ragged movement, Prime Minister Adil Abdul-Mahdi announced his resignation. The whole, intentionally sectarian political structure that was designed and installed by the United States after the 2003 invasion looked set to collapse.

Washington’s decision on December 29 to bomb the KH sites along the Iraqi-Syrian border threw a hand-grenade into that chaotic, but strongly anti-Iranian, political maelstrom. Two key Iraqi Shiite leaders who had implicitly supported the anti-Iran protests, the much-revered Grand Ayatollah Ali Sistani and the factional leader Moqtada al-Sadr, were quick to express public condemnation of the American raid. As did Prime Minister Abdul-Mahdi. All were united in decrying not just the December 29 raid itself but also the fact that Washington launched it despite the fact that Abdul-Mahdi, after being given advance notice of it by Defense Secretary Mark Esper, had specifically asked Washington not to launch it, as he was quick to inform the Iraqi people in its bloody aftermath.

And, of key significance for Americans, Iraqis, and others, throughout these recent days, no one in the U.S. government has even bothered to produce any evidence that might link KH to the December 27 incident in Kirkuk. Instead, the December 29 raid was described throughout by U.S. spokespeople as being intended, in a broad, unspecified way, to “restore deterrence” and to “send a message to Iran,” which has many political and military ties with KH, although operationally KH works in close coordination with the Iraqi military.

This idea that “restoring deterrence” can provide, on its own, any kind of valid basis on which to launch lethal military operations is a clear mark of an aggressive bully, as we have seen on the numerous times that Israel has used it to justify military operations against Lebanon or Gaza. And such operations seldom (if ever) have the desired effect of bending the targeted population to the aggressor’s will. Instead, they push the targeted population into a deeper and tougher resistance; and this is what seems to be happening inside Iraq.

It is unclear what the mission of the latest U.S. troop reinforcements in Iraq will be. The original rationale for sending U.S. troops back into the country in 2014, after their agreed-to withdrawal in 2011, was to deal with the extreme threat posed by ISIS. Over the past five years, ISIS had been almost wholly defeated, at massive cost, in both Iraq and Syria. But now, can the previous, painstakingly navigated anti-ISIS coalition — which included the United States and the governments of Iraq and Syria, along with their allies (including Iran) and some of their opponents (like the Syrian Kurds) — be preserved at all? What would the region-wide fallout from that be like?

Hanging over this, too, is the question of the continuing confrontation between Iran and the United States. As statements from U.S. officials have made clear, the major rationale of the December 29 raid was to curtail the capabilities and influence of a militia, the KH, that is seen in Washington only as an Iranian proxy; and therefore to curb some of Tehran’s regional influence. (This agenda has also for years now been actively promoted by Israel.) Given that the December 29 raid has backfired on Washington so seriously within the Iraqi political system, will Washington now choose to double down and get into an even more overt confrontation with Iran?

Let us hope not. Regional and international politics would have great impact on any such scenario. Within the region, an adventurous and politically and legally embattled Israeli prime minister might be eager for more confrontation between Washington and Tehran, but no other significant regional power would welcome it. At the global level, Washington is likely to receive not support, but condemnation, for the recklessness of its actions in Iraq. Once foreign ministries around the world get back into action after the New Years’ break, we are likely to hear of plans by numerous governments that aim at de-escalating the crisis.

Another international factor, little noticed amid the hubbub inside Iraq: On Tuesday, the Russian, Chinese, and Iranian navies wrapped up a four-day joint exercise in and around the Strait of Hormuz. This was the first time since the fall of the Shah in 1979 that the Iranian navy had conducted a joint exercise with any other partner. As it started, December 27, Iranian Rear Admiral Gholamreza Tahani declared that, “The message of this exercise is peace, friendship and lasting security through cooperation and unity … and its effect will be to show that Iran cannot be isolated.”