It’s been eight months since President Obama launched a military offensive against ISIS targets in the Middle East. It’s been four months since the president publicly called on Congress to authorize the ongoing mission. It’s been three months since Obama used part of his State of the Union address to urge lawmakers to take action. It’s been two months since the White House, at Congress’ insistence, sent a draft resolution to Capitol Hill for consideration.

But as of now, Congress intends to do literally nothing. Lawmakers can’t agree on the scope of a resolution authorizing the conflict, so they’re prepared to simply take a pass.

That does not mean, of course, that the mission against ISIS must cease. On the contrary, Obama continues to launch airstrikes on ISIS targets and help lead an international coalition. He’s just doing so without any real limits or legal authorization. Congress has effectively told the administration, “Go ahead and wage war. We’re staying out of it.”

But while Obama uses force against ISIS, the president is also working with an international coalition to prevent a war with Iran. Indeed, the White House has had considerable success, helping create a diplomatic framework, embraced by most U.S. allies, that would block Iran from acquiring nuclear weapons.

And wouldn’t you know it, all of a sudden, Congress has decided to leap to action, reasserting its foreign-policy role in such a way as to possibly kill the international agreement. Sen. Chris Murphy (D-Conn.) told Greg Sargent he’s concerned about the obvious double-standard.

“I’m first in line to reassert the power of Congress to stand next to the executive on foreign policy,” Murphy [said]. “We have a Constitutional obligation to approve or disapprove of the war against ISIS. We do not have a Constitutional obligation to approve or disapprove an executive agreement with Iran.”

Murphy notes, however, that a Congressional vote will be necessary to approve any permanent lifting of Congressional sanctions, which makes a Congressional vote on an Iran deal inevitable. […]

“There’s clearly a double-standard,” Murphy argues. “Congress wants to be all over his diplomatic engagement, while appearing eager at times to stand aside when he intervenes militarily.”

This is such an important and frequently overlooked point.

If lawmakers want to take an institutional stand in support of Congress’ legitimate role in matters of national security, great. The system is designed to have checks and balances for a reason, and if the legislative branch wants to share the burden of responsibility on matters of life and death, it’d be a welcome development.

But what the Connecticut Democrat told Greg is exactly right – Congress can’t be fickle about it, taking an interest to block diplomacy, but looking away when it’s time to authorize an ongoing military offensive abroad.

“Congress should be spending its time debating an AUMF,” Murphy added. “We have a war going on in Iraq and Syria that is unauthorized and extra-Constitutional. We should be voting on an AUMF, which is required by the Constitution, rather than debating an Iran nuclear which hasn’t even been signed.”

If anyone, in either party or either chamber, can present a coherent counter-argument to this, I’m eager to hear it.