In order to understand that the current situation is not normal, I decided to compile how often the terms "protectionism," "trade friction," and "trade war" are mentioned in articles in the Nihon Keizai Shimbun morning edition newspaper. Figure 1 shows the results of the aggregated number of hits when I looked up each of the terms in the 29 years between 1991 to 2019 (up to July 10) using Nikkei Telecom.
During the early 1990s, both the terms "protectionism" (blue line) and "trade friction" (orange line) are mentioned relatively frequently, but the mentions of protectionism can be explained by the stagnation of the world economy following the end of the Cold War, and the mentions of trade friction can be explained by the Japan-US trade friction. Protectionism is mentioned frequently in 2009 when countries pursued protectionist policies following the bankruptcy of Lehman Brothers in the previous year. An article published on November 22, 2009 reads, "According to an investigation by the World Trade Organization (WTO), after October 2008, when the financial and economic crises intensified, 52 countries and regions implemented a total of 290 protective trade measures." This was due to the increase in temporary protectionism following economic shocks, so during this time, the term "trade friction" is rarely mentioned.
Even during the collapse of Lehman Brothers, the number of search hits for "protectionism" was 145 in 2008 and 349 in 2009, but in recent years, the numbers jumped from 61 search hits in 2015 to 278 search hits in 2016, then to 595 search hits in 2017 and 685 search hits in 2018. Furthermore, in contrast with the period during the Lehman Brothers collapse, the recent movement toward protectionism is also causing trade friction. As proof of this, the number of search hits for the term "trade friction" jumped from 37 hits in 2016 to 82 hits in 2017, with an explosive increase to 1,470 hits in 2018, surpassing mentions of protectionism. In addition to that, the use of the term "trade war" (gray line), which was very rarely used in the past, has increased dramatically. This alone shows how different the current situation is, at least compared to the past 30 years or so, and how much of a serious problem this is.