Adding extra tariffs on roughly $550 billion worth of Chinese goods is "hitting low-income Americans especially hard" and "an attack on US exporters", O'Rourke wrote in an article published on Thursday on Medium.com, a blog host website.
The tariffs "have driven up the price of imported intermediate parts, made the dollar less competitive, and caused other countries to retaliate against us with their own tariffs", he said.
US goods deficit with China stood at an annually adjusted $30.2 billion in June, widening from $30.1 billion in the previous month, according to the Commerce Department's latest report, Xinhua news agency reported.
"(President Donald) Trump started his trade war with China to reduce the US trade deficit, but the deficit is rising, not shrinking," said O'Rourke.
US overall trade deficit increased to $982.5 billions in the second quarter, and trade chopped 0.72 percentage point from the 2 per cent GDP growth in the three-month period, according to the Commerce Department's revised GDP report released on Thursday.
O'Rourke in his article also highlighted the tariffs' harm to the US agriculture sector.
The tariffs, he said, "have been a disaster for American farmers and ranchers, destroying their long-standing relationships with customers abroad and forcing many family farms into bankruptcy".
( With inputs from IANS )