The Nation posted an article by Elie Mistal which is, I think, intended to roust the indignation of its readers against this not real emergency. Mistal sketches 3 scenarios to thwart execution of Trmp's proclamation. Two of these involve litigation. The third is congressional "termination". Hold that thought: US constitutional case law affirms immediate effect of presidential proclamation. Hitch that wagon to two horses --Patriot Act and re-authorizations, including extraordinary powers delegated to the executive branch by US Congress since 2002, and the bottomless DOD budget harnessed with EOs.

I'm 99% certain litigation will go no where, except to stay pending judgment (in the popular imagination) which will ultimately rule in favor of the POTUS inter alia. Furthermore, in arguing against Trump pretext Mistal includes a link to CNN collation of proclamations in xer estimation "--which, again, are stupid--". Mistal declines to explore eminent domain orders, of course.
Trump's wall would be the 32nd active national emergency, illustrated

In fact, the US has been in a perpetual state of declared national emergency for four decades, and the country is currently under 31 concurrent states of emergency about a spectrum of international issues around the globe, according to a CNN review of documents from the Congressional Research Service and the Federal Register.

Adam Schiff, Mueller's puppet master, is an incompetent reader of US history and case law. For example, the Emancipation Proclamation (which proceeded from a series of controversial congressional acts confiscating "enemy" private property) has no relation to Youngstown (1952) union-busting or to oblique definitions of "national security" and "national interest" measures funding the GWOT which the US Congress has indeed endorsed with unanimity.

House Intelligence Committee chairman Adam Schiff told CNN's Jake Tapper [!] on "State of the Union" on Sunday that Trump doesn't have the authority to declare an emergency. "If Harry Truman couldn't nationalize [sic] the steel industry during wartime [sic], this President doesn't have the power to declare an emergency and build a multibillion-dollar wall on the border. So, that's a nonstarter."

The salient point in this exercise is, a whole lot of Americans have no idea what they've got themselves into. That ignorance is as much a problem for the "union" as is the absence of any coherent goal besides the benjamins and Anyone Buttrump executing legislation by feckless sessions of Congress that they have install.

Diversity is the key to economic and political evolution.