if you were a political leader

I would generally have policies where people are free to act as they wish as long as they do not infringe upon the rights of others. Then, basically, welfare towards our fellow citizens would largely be the repsonisbility of private social groups and individuals, rather than the government. But there will still be a government safety net for the down-trodden. Take the government out of running people's lives. That said, everybody would be responsible to pay taxes for shared services, such as defense of the nation, a public treasury so different parts of the country will not use different currencies, and then local governments can have freedom on how they want to run their communities as long as they follow the basic guideline of allowing people to live as they please so long as they do not infringe upon the rights of others to live as they please. I know the real world isn't this simple, but I'd like it to be a nation that is liberty-friendly - and the government compliments liberty, not control it.

I would follow the U.S. Constitution. It worked very well for a long time and it's only when it's being perverted that it isn't effective. Freedom is what makes any nation great.

If I am the lead of a country,policies will be imitative of USA.

I would have thrown the military out of the window because hteir is no need for military forces in the world if just everybody agrees it.