What did Donald Trump do today?

He reversed course on whether his administration would comply with a judicial order to reunite migrant families.

Today, the Trump administration went to court insisting that it could not comply with a judge's order to reunite 100 or so young migrant children with their parents by next Tuesday, or the more than 3,000 other similarly situated children by the deadline of July 26.

Yesterday, even as the number of separated children continued to rise rather than fall, the Trump appointee in charge of the reunification effort insisted that he would "fully comply" with the order by the deadline.

Part of the proceedings today were delayed until Monday because a government lawyer said she had dog-sitting responsibilities that prevented her from working on the effort to reunite seized children with their parents. 

Why does this matter?

• Presidents are subject to the rule of law.

• Lying for public relations purposes is bad.

• Volunteer pet care is less urgent than reuniting thousands of jailed children with their parents.