The GOP presidential front-runner Donald Trumpwon a sweeping victory in the Indiana Republican primary on Tuesday, dealing a heavy blow to his rival Ted Cruz, who dropped out of the race later that night. Trump cleared his way to the Republican nomination for the 2016 US presidential election. Chairman of the Republican National Committee Reince Priebus declared Trump to be the party's "presumptive" presidential nominee and called for unity against Hillary Clinton.

Trump's breakthrough in the Republican primaries has caused a sensation in US politics, public discourse and the international community. At the beginning of the race, most analysts and observers believed that Trump was no more than a clown. A few months ago, few people believed that the endgame would be between Trump and Clinton.

Although many analysts still insist the odds are in favor of Clinton, they are somewhat uncertain about the final result. Trump's performance in the primaries has proven them wrong. Why can't the unstoppable candidate prove them wrong again?

If Trump really captures the White House, what will it mean? This scenario is becoming increasingly serious.

The US traditional political elite and media have long ignored the drastic changes in US society. Rising against the repression of the GOP establishment and the mockery of US mainstream media, Trump will substantially shake the conventional US' way of operation. Acquiring more authority from US society, he will be expected to bring in more reforms, that might change many established policies.

According to Trump's current policy proposals, a Trump-led US might be inclined to isolationism and attach more importance to "America First," and American economy. Ideology will be downplayed. Washington might engage in more squabbles with its free-riding allies, and tighten up its immigration policy which as a result will upset the Latin Americans. After enjoying massive trade surplus from the US for years, China and Japan will be demanded by Washington to widen market access.

If Clinton is elected, the US politics will be more predictable and revolve around the previous orbit. Although Washington is expected to be tougher on Beijing, its policies are controllable. While Trump represents pragmatism, Clinton prioritizes ideology in political affairs. To China, this distinction is more important. Clinton sees the Sino-US relationship from a traditional perspective, and Trump from a much newer viewpoint. The latter will bring changes to the Sino-US relationship.

However, a single individual is unable to dictate the Sino-US relationship and the US domestic issues. If elected, Trump will be restricted by interior and exterior realities. As a result, he will be subject to "transformation." In fact, the "transformation" is an interaction between Trump and the US. He will be more prudent if taking office in the White House. In fact, compared with the past, Trump has become more attentive to his words.

If elected as the president, Trump's ability to take action and make change will not be as great as suggested by his unrestrained performances. He has already "created history" today. Even if he is defeated by Clinton, Trump has deeply impressed the US politics.

The US election pattern is basically finalized: Trump versus Clinton. It will be a super political show, attracting unprecedented attention and closely bound up to the world interests. While Trump is a practical business tycoon subverting US political correctness, Clinton is a former secretary of state and former first lady, representative of US political correctness and the mainstream thoughts.

Improving strength is the most reliable way to respond to the US uncertainties. We believe that no matter whether Trump or Clinton prevails, they will see a "China with strength" from different perspectives.