David M Jackson

USA TODAY

Again taking to Twitter to bash a business, President Trump attacked the Nordstrom department store chain Wednesday for dropping daughter Ivanka's fashion line, drawing criticism for mixing government and his family's business interests.

"My daughter Ivanka has been treated so unfairly by @Nordstrom," Trump tweeted from his @realDonaldTrump account, then retweeted on the official @POTUS account. "She is a great person — always pushing me to do the right thing! Terrible!"

Trump's critics said the president has, again, used his position to threaten businesses in an unfair and perhaps illegal manner. Norm Eisen, chief ethics officer for President Obama and co-founder of the organization Citizens for Responsibility and Ethics in Washington, broached the idea of a lawsuit.

"Outrageous," Eisen tweeted. "@nordstrom, others injured should consider suing, incl. under CA Unfair Comp Law, forbidding "any unfair biz act." I will help!"

White House spokesman Sean Spicer said the president was responding to "an attack on his daughter," and "he has every right to stand up for his family."

In past months, Trump has used Twitter to criticize car companies for plans to move operations overseas and defense contractors for product costs; he also urged consumers to buy L.L. Bean products after a member of the Bean family was accused of making excessive contributions to a pro-Trump political committee.

Nordstrom announced last week it would not sell this season's Ivanka Trump merchandise. While a group called "Grab Your Wallet" has urged companies to boycott any and all Trump products, the Seattle-based department store chain said it based its decision on sales performance.

Trump's opponents raised a longtime concern that the president is trying to leverage his position to benefit his family and business interests.

"Trump uses power of the presidency to shill for Ivanka’s merchandise," said the website ThinkProgress.

Others compared Trump's tweet to President Harry Truman's threats on a music critic who drubbed his daughter's concert performance.

Ari Fleischer, the former press secretary for President George W. Bush, also tweeted about Trump's outburst: "This is something a father would say. It's not the type of thing a President of the United States should say."

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Trump blasts Nordstrom after it dumps Ivanka's fashion line

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