Jefferson Davis, Confederacy President was forced out of U.S to live in Glasgow.Is it any way for us in US to treat leader of 1/2 the Nation?

Jefferson Davis was not "forced out of U.S to live in Glasgow", After his release from prison and pardon Davis lived n Memphis, but had financial pressures and made many trips to Cuba and  Europe looking for business oppertunties.  At one stage he stayed as a guest of James Smith, a foundry owner in Glasgow, who had struck up a friendship with Davis when he toured the Southern States promoting his foundry business.  In1870 he was given title to Brierfield Plantation at Davis Bend Mississippi.

In 1877, Sarah Anne Ellis Dorsey, a wealthy widow and writer whom he and Varina had known from childhood and who supported the Lost Cause, invited Davis to stay at her estate and plantation house, "Beauvoir", which faced the Gulf of Mexico in Biloxi, Mississippi. She provided him a cabin for his own use as well as helped him with his writing through organization, dictation, editing and encouragement. Davis refused to accept overt charity, but agreed to purchase the property at a modest price ($5,500, payable in installments over three years). In January 1878 Dorsey, made over her will  in order to leave her remaining three small Louisiana plantations and financial assets of $50,000 (equivalent to $1,270,000 in 2017) to Davis , by which time both the Davises were living at Beauvoir.

It was fine treatment towards a traitor who lead an attempt to dissolve the union and destroy our country. He should have been a wanted man and imprisoned, but he got to live out his days outside of a jail cell. He got way better than he deserved. 

Indeed.

Davis should have been hung to death for the traitor that he was.

The man should have been grateful he wasn't hung. . 

He wasn't the leader of half the nation. He was president of the Confederacy which had declared itself an independent nation. 

From what I have read, Davis was a 'guest' in Glasgow.  Jefferson Davis committed treason; as secession was not constitutional.  Davis was never tried for his insurrection and was released from prison after two years.