Well, then you’re getting into the use of the word “radical.” Japan’s government does have a list of radicals whereby you can match every kanji used in compulsory education with its designated radical.
But that’s the meaning of “radical” where each kanji only has 1. So the radical of 務 is 力. That kanji has no other radicals under that system.
And when Japanese people use paper dictionaries to look up kanji, they would find 務 under the section for 力.
That’s obviously quite different from Jisho, where you can choose a bunch of different elements that exist inside the kanji beyond the one radical and use that to look them up. Those other elements are not standardized anywhere.
Is the left side of 務 made of マ and オ (just grabbing some parts that look similar)? Or is it one element that is 矛? There’s no standardized answer to that question. You could trace things back to how they were originally written when they still looked like pictures, but then you’d occasionally end up with conflicting situations between visually identical modern kanji elements. The 務 example probably isn’t the best one, since most people aren’t going to have trouble decomposing it, but yeah.