WASHINGTON — President Obama has praised the coordinated response to Colorado’s wildfires and said trying times bring Americans together.

Obama was in the state Friday for a firsthand look at the damage after he declared the situation a major disaster and promised federal aid. More than 30,000 people have been evacuated in what is now the most destructive wildfire in state history.

‘‘When we see our fellow citizens in trouble and having difficulty, we come together as one American family, as one community,’’ Obama said Saturday in his weekly radio and Internet address.

The federal government has provided firefighters, fire engines, and aircraft, including 19 air tankers, to assist in fighting the fires in Colorado and other Western states.

Obama’s focus on the Colorado fires came at the end of an eventful week at the White House, capped by Thursday’s Supreme Court decision upholding the health care law and congressional passage of two of his priorities — a highway construction bill and an extension of lower student loan rates.

Obama acknowledged that choosing the fires as the topic of his weekend address was unusual, but said it was an opportunity to focus on the problem facing the people of Colorado.

In the Republican address, Senator John Barrasso of Wyoming took aim at Obama’s health care law, arguing that it has not lived up to its billing and vowing that Republicans would work to repeal it.

‘‘Each broken promise proves that the Supreme Court’s ruling did absolutely nothing to improve the president’s failed health care law,’’ he said.