Why did the united states support sugar planters in their attempt to overthrow queen liliukalani?

The US overthrew Liliuokalani because she didn't keep the treaty that the former leader of Hawaii had with the planters. This treaty stated that the planters could plant sugar crops in Hawaii. When Liliuokalani came to power she was anti-american and didn't want the planters there, so the americans overthrew her.