The BRICS aren't outside US sphere of influence. India is squarely within it. South Africa is very friendly. Brazil is friendly. Russia had been friendly under Bush and early Obama. And China's our number one trading partner - hardly an enemy, except in the fevered imagination of anti-China hawks.

The US is clearly in a state of decline and the soft power it’s able to wield today is considerably less than it held in the past

I gotta disagree. Absent a serious geopolitical rival - the USSR - we've rapidly expanded our influence across Eastern Europe, Latin America, and East Asia.

India's a great example. They were squarely in Soviet influence in the 80s and fell out rapidly with the disintegration of the Soviet sphere.

Same with Argentina, Yugoslavia, even Cuba and North Korea. Countries that flirted with Socialism prior to '91 fled from it afterwards. Countries committed to Marxist Leninism thawed to capitalist experimentation. All that came out of American think tanks and propaganda mills and lobbying firms.

While it’s true that the US was pretty brazen in invading Korea and Vietnam, it was also able to control the narrative better and did things either covertly or had some sort of pretense for it, and the postwar order also involved significant economic investment in places like Europe, Taiwan, South Korea, and Japan, all of which helped generate soft power.

The US lacked global financial and technological dominance in the 60s and 70s. The catastrophes of Korea and Vietnam were far realer in the moment. It wasn't until Reagan and Clinton they they were massaged away.

The US gained influence and continues to gain influence through it's corporate expansion. The US Federal Government might be losing its grip, but that's less and less the seat of real material authority.