At the start, it was Smith's business, but after Gao Guang took it over, he began to scale things up.
Now, it's Gao Guang's business, and Gao Guang thinks it's about enough, but Eric wants to scale things up even more.
You can choose when to start a war, but you can't choose when to end it—this adage applicable to warfare also applies to Senator Simmons.
Of all people, Simmons just had to pick on Smith, and now, not only has Gao Guang stepped in to strongly defend Smith, but Eric has insisted on upping the ante for Gao Guang,
Eric is dead set on letting Simmons feel the iron fist of the capitalist.
Now, it's Otto and Eric who are persuading Gao Guang.
Otto must have a considerable role in this, as assassinating a crime boss would be somewhat beneath him; his reputation as Shadowless wasn't built in the underworld just by being tough, nor was his influence obtained through sheer violence.