This article misses a huge point- at the time, Tariffs and duties were our only taxes and the highest were just about 5%. For the most part (except for some very progressive presidents) they weren't done for protectionism, it was simply the only means to tax prior to the 16th Amendment.
Now, the average American pays over 50% in taxes, fees, and government imposed surcharges before we even consider those tariffs. Americans are Taxed Enough Already and taxation is theft. There is nothing 'American' or 'Conservative' about adding to the burden of the American taxpayer by slapping on another 25% tax on what he buys in an attempt at central planning. The manufacturing world is also changing. Even domestic manufacturers rely on foreign products that are simply too expensive to make here, so as we've seen, this is hurting domestic manufacturers too. (example, Snap-on just announced they are closing their plant in the US and moving it to Mexico).
There is a reason the Constitution didn't make the process easy to add taxes. Article 1, Section 8 puts this responsibility in the hands of Congress- not the President. A couple of laws do allow the President to enact minimal tariffs in times of emergency, but all those laws require the President to still submit them to Congress within 60 days, something this President has not done.
There is nothing American about that at all. And certainly not Conservative.