Exploring the timeline of American history, it is clear that the USA was a laggard in terms of innovation until quite recently. At the turn of the previous century it was not uncommon for promising young students to travel to Europe for higher studies. But with the advent of the Second World War and the exodus of the Jewish people from Europe, America gained ground and became a scientific leader. Also potential rivals such as the UK, Germany and France got embroiled in problems of their own which prevented them from retaining their earlier leadership position, thus helping America prosper. Business innovation typically requires the combination of three stakeholders- academia, public sector and private industry. Major scientific breakthrough and their scaling has required these aspects. Thus beyond just helping startups get seed funds or tax breaks or increased investment, a more comprehensive plan is needed. This will reduce the time lag between ideation, implementation and scaling. 

Source:  http://www.forbes.com/sites/gregsatell/2015/12/18/we-need-to-accelerate-innovation-heres-how/