They could shut down the Country if it came to that.
They could....however, if truckers effectively shut things down, I suspect "emergency powers" aka a form of martiial law would be granted to sieze their trucks - at the point of a gun - and give to those willing to drive. Illegals, those granted asylum, minorities, other "disadvantaged."
Who, btw, might not have the option of declining the opportunity.
The military would fill the emergency transport gap until the commandeered trucks rolled again. jmo