Just as in Canada, there is likely to be a total ban on any liquid from China. Period. But the United States has Johnson Creek making liquids in a facility that the FDA could monitor for standards. So we do have a U.S. liquid maker (undoubtedly using ingredients from everywhere, but it's the final liquid that counts and would be tested!).
And I agree that the easiest solution to allowing e-cigs is to mandate a single-unit, non-refillable, non-rechargeable e-cig of known, specific nicotine strength. Right now, the Ruyan Jazz, Njoy Weekender and one from Gamucci, I believe, are on the market. To me, they clearly have the advantage of being easily regulated.