Its an emergency measure, in case anyone in power is hamstrung or reckless enough to unintentionally -or- to the amazement of everyone reasonable, intentionally drive us into default and we need to reset and stabilize the economy. Theres a reason why the post-civil-war amendments were passed, because of elements determined to drive us over the edge and into disunion. They have more technology, better transportation and communications, and superior firearms behind their attempts this time. That does not change the validity of the Constitution.
And the situation we are in in terms of our global economic impact does not change. So its not just our economy that crumbles, but every nation we have chosen to support. Who benefits from that other than oligarchs, regional thugs, and regimes determined to oppose our influence. The civil war was actually the only time in the past a change of government like that *could* have been initiated without influencing world matters and causing a scenario where much worse consequences unfolded across the world in the style of the initiation of the First World War. After the World Wars and the collapse or dissolution of the British Empire, the Qing Dynasty, and the insurgent Nazi Reich, Japanese Empire, and Soviet Union, we were it.
We built up the globe, with difficulty and opposition, and it was messy, but ripping the rug out now means something far harsher will step in as a consequence of the famines and structural failures already evident. We may not be able to fix everything right away with our Allies, but we can fix this.