Iraqi leaders are claiming a Republican-backed US law is part of a plot to break up the country

A Republican proposal to directly arm Sunni tribes and the Kurds in Iraq in the fight against ISIS without oversight from the Iraqi central government has raised fears and anger in Baghdad, where officials fear the US may be aiming to break the country apart.

Texas Republican Congressman Mac Thornberry's proposal to directly arm various nonstate forces in the fight against ISIS has inspired a swirl of conspiracy theories and rumors among Iran's Shiite majority, some of whom believe that the US wants to partition Iraq into three competing states, Tim Arango writes for The New York Times.

Thornberry, a member of the House Armed Services Committee, drafted a plan that would label Sunnis and Kurds as distinct "countries," in order "to comply with American laws on direct military aid," the Times reports. Thornberry said his intention was not to balkanize Iraq but rather to get around legal hurdles that would prevent the US from arming various nonstate factions within the country.

Still, the Shiite majority in Iraq has responded with indignation and distrust to the proposal. Iraqi news outlet Al Bayyna ran a front page story with the headline "Congress proposes to deal with Kurds and Sunnis as two states," the Times reports.

The image accompanying the story was an illustration of a chained Iraq split into three different nations: Sunnistan, Kurdistan, and Shiastan.

The influential Shiite cleric Muqtada al-Sadr has also threatened attacks against US interests should Thornberry's plan to directly arm Sunnis and Kurds comes to fruition.

"In the event of approving this bill by the US Congress, we will find ourselves obliged to unfreeze the military wing and start targeting the American interests in Iraq - even abroad, which is doable," a message posted to Sadr's website read.

The criticism from Iraq's Shia highlights the difficulties the US is facing in implementing a strategy to defeat ISIS. The US hopes that it will be able to work with a network of reliable ground operators assisted by the Baghdad government that would fight alongside the Iraqi Army with support from US air power.

This strategy has run into numerous problems. The Iraqi military has proven less than capable on the battlefield. And the Iraqi government has been unwilling to arm more effective militias run by Kurds or the Sunnis out of a fear that the rival groups will use those weapons to launch military campaigns for their own autonomy or even, ultimately, independence. Baghdad also believes that it is capable of rolling back ISIS through a combination of the national Iraqi military and Iranian-backed Shiite militias.

But the ongoing battles against ISIS show that neither the Kurds nor Baghdad have any real desire to fight ISIS in its heartland in the Sunni portions of western Iraq. Without a concerted effort to dislodge ISIS through either the Iraqi military or direct arms to the Sunni tribes, ISIS is unlikely to be fully defeated in the country any time soon.