The guns of August are cocked and ready. Donald Trump is wondering aloud whether to fire his attorney-general, Jefferson Sessions. The US President is also musing about who will rid him of the troublesome special counsel, Robert Mueller. That, too, must eventually end in Mr. Mueller’s exit. Both are a question of timing. My hunch is August. But it could be months away. Or tomorrow. Mr. Trump will do what he must to block the investigation. Mr. Mueller has broadened his probe to include the Trump Organisation’s financial dealings with Russia. There is ample cause to scrutinise Mr. Trump’s business dealings with Russian. The further Mr. Mueller progresses, the more Mr. Trump panics. His reactions betray his motives. Sooner or later, serious investigators end up following the money. It can only result in a collision. The question is whether the US republic can walk away unscathed. Having recused himself from anything related to the Russia investigations, Mr. Sessions cannot fire Mr. Mueller, and his deputy, Rod Rosenstein, is unlikely to do so either., At this point a constitutional crisis would erupt. America’s founding fathers created a system based on laws, not men. But it is down to people to uphold the system. In theory, there is nothing stopping Mr. Trump from doing whatever he likes. Most constitutional lawyers say you cannot indict a sitting President. If Mr. Mueller were sacked no court would reinstate him. The same applies to Mr. Sessions.