Republicans in congress support it. It is not about congress not having abstract spine.
It is about republican congressmen actively supporting all of this.
And bonus, they don't have to go on record voting for all the things they support but know are immensely unpopular.
Plot twist: The Dem leadership (Schumer, Jeffries, et al) also supports this.
That's why their main complaints have been procedural: "Why didn't you come to us first with your plans?". And why they slow-walked the vote on a war powers act.