Chris Murphy, a Democrat, is a US senator from Connecticut. The opinions expressed in this commentary are his own; view more opinion at CNN.

(CNN) Washington is agonizingly slow at learning from its mistakes. Especially in the Middle East. Over the last decade and a half in that critical but chaotic part of the world, the United States has repeatedly witnessed the limitations of using the blunt instrument of American military force to solve complicated political, social, economic and religious conflicts. There is, of course, no better example of this failure to understand the limits of American military power than our decade-long disastrous invasion and occupation of Iraq. And yet we are now back to making the same mistakes, this time in a less well-known country called Yemen.

For three years, the United States has supported a coalition led by Saudi Arabia that is waging war inside Yemen, trying to oust a rebel government made up of members of the Houthi tribe. Our role in the coalition is significant -- we sell bombs and weapons to the Saudis, we help them pick targets inside Yemen , and until recently, we refueled their planes in the sky.

To anyone paying attention, it's clear that the United States is engaged in a war in Yemen. And yet this war has not been authorized or debated by Congress. Our involvement started quietly under President Barack Obama, and now President Donald Trump has increased our participation. And it's not as if our participation in the Yemen conflict hasn't come with serious consequences.

Yemen has become a hell on earth for the civilians caught within its borders. More than 10,000 innocents have been killed in the Saudi-led bombing campaign since the beginning of the civil war. Targets have included schools, hospitals, weddings, a funeral party and recently a school bus carrying 38 children to a field trip.

JUST WATCHED Houthi FM: Only the US can end war in Yemen Replay More Videos ... MUST WATCH Houthi FM: Only the US can end war in Yemen 18:06

Read More