(Brandon Sun) The United States has officially served notice of its intention to renegotiate the 1993 North American Free Trade Agreement, triggering a 90-day consultation window before talks begin later this summer with Canada and Mexico.

The Trump administration rang the opening bell Thursday with a letter to the key congressional power-brokers who must now be consulted as U.S. negotiators prepare their list of priorities.

The letter itself was mundane.

It cited the need to modernize a creaky old agreement, add new provisions relevant to the modern economy, and mentioned things already negotiated in the Trans-Pacific Partnership, the deal abandoned by Donald Trump: digital trade flows, intellectual property, limits on state-owned enterprises.

It barely filled a single page and was drastically scaled back from the laundry list of complaints included in a draft version earlier this year. Some U.S. proponents of a hardball approach expressed disappointment.

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