Well, if we use most politicians' view of an oath as our model, the Pledge of Allegiance wouldn't mean much either.
Indeed. If witnesses in trials kept their oath the way politicians do we'd have Al Capone's Chicago nationwide, instead of just in Chicago, NY, CA, and DC.
But, just surmising, if any states could withdraw from the union they'd face the full might of the US military. Only a few states could do that. Alaska, for one, has oil deposits on its territory, has a couple of military bases with the latest fighter aircraft and bombers, has nukes, and is remote enough that it would be a logistic problem to support troops from such a distance. Assuming, of course, that the regiments at the various bases through out Alaska would go along with succession. The nukes could be targeted on DC as a deterrent.
And, IF Alaska did do that then they'd have to be concerned about their neighbors to the West, one of which claims that the Alaska purchase was illegal, null and void. Some of their nukes would have to remain targeted on Russia, China and North Korea.
Personally, with 47% of Americans now depending on government handouts (and that excludes those on SS after years of paying into Social Security), the Left has a huge voting block that requires only 5% or so of the fence riders to tip the balance. Which, BTW, is exactly how Obama won the last election. Pork works.